I think my answer might have been laying here in front of me the whole time. When I bag my truck, I'll need a fuel cell, like this

The fuel cell shown is 12 gallons, and its only 110.00 from Summit Racing. Of course, the tie down straps are extra.
When I change to that, I'll have to install a fuel level sending unit anyways, so i will use one from VDO Gauges, like the vdo 226008. It is set up to run on 0-90 ohms, and then I can use any fuel gauge that operates on GM vehicles.