Building a new fuel tank?

[Critter]

My current place of employment has a shop full of TIG welders and extremely talented people to run them (I am not one of those people). I have been kicking around the idea of having one of the welders help me build an aluminum fuel tank. I could cut all the pieces and tack them together then have one of the talented guys run all the beads. The reason I am thinking about doing this is A) because I am going to be running an LS motor and might want a low sump on the tank for an external fuel pump. And B) just for the heck of it.

I'm picturing something simple and square, with the dropped down pickup and return tube...like this.


My question is what sort of baffeling should I put in? Does anybody have any pics of the inside of a nice aluminum fuel tank/cell for comparison? Also the cell pictured above is made from 0.100" thick aluminum, I would probably use 1/8" because that's what is around the shop. I'm guessing that would be strong enough material for underneath a blazer, right? I'm not going to be rock crawling or anything, just street and light trail use. Should I coat the inside with anything? Any ideas and thoughts are appreciated.