Coyote swap into 72 F100 questions

[CurtisD]

New member and first post. Thanks for having me. I'm building a 72 F100 short bed 2wd. It has a Fat man fab MustangII front suspension with a flip kit on the rear with discs all around. I want to swap a Coyote 5.0/6R80 combo in for the 390FE/C6. I have no experience and have never even ridden in a vehicle with one of these engines. My question is; Should I buy the stuff new with new wiring, ecu, harness, etc. Or I can buy an engine, trans, and all the take out harnesses and computer from a place located several hours south in Lyons GA called the parts farm. I can buy it set up to crank and run on the pallet it comes on! I like the idea of being able to run the motor when it is shipped and know it works as it will be a used engine. However, I don't want to waste money on any wiring or ecu that I may replace with something newer or simpler like the power pack you can buy from Ford and trans controller from PA transmissions for example. Any and all advice will be appreciated!