Sorry but I despise the FE motors. Cool just not my cup of tea. Would go 351 c or w but need overdrive and this is a cheap project. Doing it in tandem with my square body crew cab. 4x4 shortbed build.No LS. No 4BT or 6BT. How about Boss 9 or old school FE? Sorry, die hard big block Ford fan. The Boss 9 would be expensive, an old 390 much more affordable and has many Shelby Goodies available. Even a Coyote or Godzilla would be preferrable to an LS. I will admit, the LS is a good engine, but there are many just as good if not better.
At the end of the day though it is your truck, not mine. If I won the lotto I would buy the truck from you and save it from being defiled by a Chevy or Cummins.
In spite of all that happy for you and hope it is a fun project!