The cheapest way to do this is with a complete wrecked vehicle to pull parts from and use ALL the original parts (computer, wiring, etc.). The dash will get tricky, but this isn't insurmountable.

While not the same, we did a 5.2 Magnum swap into an 84 Ramcharger. We started with a wrecked 96 Dakota and swapped EVERYTHING, modified the fuel tank, and used a 92 Ram instrument cluster. The cost of the swap, our labor. We were able to sell off parts from the Dakota to cover the parts cost.

I would consider any of these swaps into older cars, but I think I'd look at the welded aluminum tanks and see if those companies offer one for fuel injection, especially one that will accept the factory pump assembly.