I was wondering what would be the best year of a 5.0 out of the explorer/mountaineer do to for my motor swap this will be my first time doing a motor swap and everywhere online says it is pretty much plug and play but I want some advice to make it a little easier to understand.

 

All you need to know here.
https://www.therangerstation.com/tech/
Best to buy the donor to have everything you will need for the swap. That will be the hardest part.. Good luck.