Sam have ya considered a battery selector switch? Gives you choice of start battery as well as charging capability to each.

Auto bilges have been known to kill batteries. No need for such a device if your not mooring. Unless ya just want to be cool and in that case you'll want to buy one that provides a BIG decal for your boat.(lol)

Get the tank out so ya can inspect that mother for dirt, gunk and, other nasty none breathing stuff that forms when water mixes with gas and oil. While yer at it, put a canister type fuel filter inline. Get one that provides a great BIG decal for the boat. :-)

Minor update.  Despite good intentions, I didn't touch the boat at all over the holiday.  Yeah, that lazy.  Went out today to drain the gas tank.  Cut the fitting off the fuel line on the motor end, and then put the hose down into a barrel and pumped the ball.  That worked... not at all.  That ball need a closed end to work I guess?  It doesn't function as a running pump.  Either that or the pump ball dealy is screwed.  Either way, wasted effort.  F-
 
Went to the local hardware and got 20' of clear 3/8" ID tube.  Going to connect that directly to the tank and siphon it out.  Figure I'll have a decent chance of not getting a mouthful of gas if I can see through the hose.  Will report back on how that goes.  Or you'll see me on the news in the burn/explosion ward.  

Had a helper today, so I decided to get after that pesky gas tank.  Pictures to follow.  Lessons learned: 
 
- any time you mess with gasoline, expect to bathe in it
- gas fumes may not always asplode, but they REALLY aren't fun to breathe for very long
- if you think you got it all out/empty, you didn't
- gas doesn't taste very good at all, and the fumes don't taste a whole lot better
- BOAT BUILDERS CAN EAT A GIGANTIC BAG OF UNSPECIFIC ANIMAL GENITALIA
 
I didn't get any gas in my mouth, despite having to resort to old school hose_siphoning.  But I did get a couple good chomps of the fumes to get the siphon started, and that wasn't really all that fun.  Drained a good 15 gallons from the tank before it stopped, and assumed it was empty.  See #3 above.  So when we finally got the **** thing over the rail, it spewed a good big gulp of fuel on my basement floor.  Lovely.  Then we had to drain it with a bucket while I held the thing on the rail.  Had another 6-8 gallons in it!  Which... going to have to attribute to the boat not being leaned back like it normally would.  
 
Anyway, several pic of the tank, plus pics of the brace removal.  And to remove those braces I had to cut out some floor.  AND I had to remove four angle-dealies that were riveted in and sticky taped to the tank.  They REALLY didn't want this thing moving.  Assuming that all those efforts are to insure the tank can't bounce around and come loose, so I'll have to figure out a way to put them back.  Likely I'll just rivet them back in after cleaning them.  
 

See how the brace here ^ stuck out under the side board?  

Three rivets drilled out of each side of the braces ^

Used a battery powered circular saw to cut away the floor.  You can see two of the L braces in this pic, which also had to be drilled out and the pried off.  

You can see in the middle picture above that these braces were pretty haphazard.  Look at that big gap and see how the brace looks like it cracked/sagged.  Then look at the first pic with the much smaller gap.  Going to take those to my metal guy and have him design me something that doesn't suck.  If I have to use steel plate there and route out the bottom of the floor board, I will do that.  No sense having flimsy braces.  
 
Couple pics of the gas tank (filthy thing) out of the boat and the mess where it was in the boat.  
 


 
 

Finish off with a pic of the mess which is my bilge area.  Look at that birds nest of wiring nonsense.  There's about 3x what you see in that picture.  Going to spend some time wiring this thing proper, and it's going to feel really good not to have slipshod wiring plaguing me.  I'm talking nice clean traces of proper colored wire with shrink wraps and flex conduit.  
 
Also a good pic of the gas filler hose, which was a NIGHTMARE to remove.  The neck on the tank is 4 or 5 inches and that hose is no joke.  Double clamped because... of the Exxon Valdez spill I guess.  Took us 15-20 mins of struggle to get that off, and I'm certain that putting it back will suck harder.  Also those rear braces are wobbly ****e, will have to re-engineer them before reinstalling the tank.  

 
Probably take tomorrow off and let the gas fumes evaporate from my garage.  I'll spend that time trying to find someone to clean that gas tank properly.  Suggestions would be well appreciated.
 

Well I cleaned the tank today.  Outside cleaned up very easily with a QVC crappy power washer.  Inside... full of bits and BS and gunk.  :(  No easy way to get at that either.  Tried some seafoam, which did loosen some of the gunk but that stuff is expensive and I don't have nearly enough of it.  Mechanic friend says kerosene.  Swish and dump kind of deal.  Thinking I'll add some BBs for added action.  Don't want to try a chain or nuts and bolts or any of the more colorful internet suggestions, since there's a float in there that works.  I'll take a couple pics of the clean tank after I go get some kerosene.  

Before I get to those pics, a small rant, and it is going to be VERY hard for me to keep this PG13...
 
The person or persons who designed the "safety" spout that is on every gas can made in the last 10 year should be found, set on fire, rolled in fire ants, thrown in acid, rolled through some more ants, and then thrown into traffic.  After setting them on fire again.  And maybe shot in the balls and stabbed in the face a few times.  Oh!  Pecked by crows.  Forgot that.  Seriously every time I touch one of those worthless POSs I go absolutely insane.  Right after I'm soaked in gas, or whatever is in the can I'm trying to use, since soaking the user seems to be the only thing those spouts are useful for.  Also, *($^  *(^&*$@(&)  &*^$T%$&^@^)*  &*(^%$*&($%)(  &*$T^@&  *($&^.  And *($&@)!
 
Okay, now then.  I found some local kerosene, and managed to clean out the tank pretty good.  Gas tank mischief managed.  Next session will be back on the floor removal.  
 



 

Looking good. 
 

Zelie Sam, as one who has just done a complete rebuild of my 1988 Sylvan Backtroller, (bought new), I know what you're going through, though I get the impression that although you want to get it done, you seem at times a little less enthusiastic. Yep! It sometimes seems overwhelming, but you'll eventually get 'er done, and the finished product should make you proud. It may have been a little easier for me, as I'm a Chrysler/Jeep/Dodge technician and a fairly proficient woodworker and DIYer.
After a bit of motor trouble and career changes, my boat sat outside neglected for 17 years, with little maple and wild cherry trees growing up in the floor. It is now fully restored, (with all heavier panels and vinyl instead of carpeting), and running like a champ. I do need to turn the bilge pump on for 10 or 15 seconds every 45 minutes or so, but I can live with that. Not bad for a 27 year old aluminum hull. Keep on keepin' on!