Fuel cell mod

[tregrad]

I have an after market fuel cell in my 72 Blazer, I bought it with it in it. When ever i need fuel I have to climb into the back, flip a hatch door open and fill it that way, total PITA for an old dude like me.
Well today i dropped the tank because im installing a new hitch receiver (Uhaul part #75914 and its burley). and want to weld a filler neck onto and run the hose up to the original neck so i don't have to climb in the bed to fill it every time. since i have it dropped I figured I might as well make sure the pump and everything looks good etc. Well when i pulled the pump and peered into the tank there is all this red s#it everywhere what seems like a sprayed in liner, not really a bladder so-to-speak but more of a liner and its coming loose on the sides and im sure its going to be harboring gas in between the folds where its peeling away from the walls.

Question:
1. How do i do this safely? My thinking is to fill it with water to the level where i want the filler welded on or even higher, drill the hole and gnarl it out to shape i want, then lower the level a bit and weld the filler neck pipe on?

2. That said, I think there will be a lot of water left in the tank between the fold where its peeling after i drain the water out, how do you dry the water out?

[hemi43]

You've already answered your own question.
Why would you want to modify a fuel cell (which you shouldn't) if the liner has failed?
The tank is scrap, so now is your chance to replace it with a proper unit.

[tregrad]

So what if i cut the top off, clean it out, reseal it and then weld it back on?

[hemi43]

Originally Posted by tregrad

So what if i cut the top off, clean it out, reseal it and then weld it back on?

If you want to waste your time, yes you could, or you could do the right thing and get a new unit.
If you need to post here asking how to weld/fix a fuel cell that gets used on public roads, then be prepared for some backlash.