The ford stock Efi is a more reliable "start the truck and go" system as it adjusts automatically. If you had the donor computer and harness...it would be a direct swap. But harder to tune with upgrades especially on what I would guess to be the speed density system you would have on your truck and possibly on the swap...maf equipped hands down would be the one you would swap but once again the stock software can only adjust so much ...however a stock 351 in that generation wasn't a power house with efi. I would go carb as its easier to tune with the planned upgrades. And less stuff to go wrong. Or go a step further with a carb style intake but with a atomic Efi setup. Ford performance I think does make a stock Efi engine harness as does many other manufacturers.
Secondly do you plan to daily drive it? Daily driver...hands down efi. Fun toy? Carb.