Gen 3 Coupe? Space for the evaporator is very limited due to the frame design. Unless you put it somewhere other than the pass side footbox. I looked at everything I could find on the market. And none fit. Other than the Siroco brand unit they provide. Mine was installed in a Coyote build and came with everything needed. But can't answer your specific question about a different engine setup. Their instructions are pretty detailed and maybe help. Even if you don't go with theirs. https://www.factoryfive.com/wp-content/uploads/2020/07/AC-HEATER-DEFROSTER-COUPE-Gen-3-REV-G.pdf