After doing tons of searching, I came up with 87-90 jeep wrangler tank. it is a fuel injection tank so it did have a baffle inside. it measures 25x 18.5 x 11. it fit in the rear area there with no cutting or modifying of the frame. I did however have to use a piece of angle iron across the back to have something for it to rest on.
There is a flange all the way around the tank about a inch wide, so I drilled 1/4 holes in each corner and just bolted it in place.
There were a few problems with putting this tank in. when I put the tank in I did it with the bed off and because it went in from the top when I put the bed on, the it hit one of the bed braces underneath. so I had to trim that back a little. Iv since concluded if I had mounted it from the bottom it most likly would have cleared. The fuel fill is only 1". and it is was right where the cross brace was as well. The only place I could find a 1" fuel fill hose, was McMaster Carr. (one could always just have a new fill welded on.) Anyway it worked out for me, but could be a problem for other installs.
The sending unit is a stock GM I think I used one from a 85 c/10. I of coarse had to modify it to fit my fuel pump and sock on it.
By the way thanks for all the encouraging compliments, I appreciate them!