If I am buying just the engine harness for my car, does it matter if it has a/c or not if my car has a/c? I mean are the a/c wires going to still be there even though the donor car doesn't have A/C? Also my car has power mirrors doorlocks, windows, and such will that matter or not when just dealing with the engine harness?

Lil more info

My Car
95 st auto
power wind, locks, mirrors, a/c

Donor car
94 st auto
no power or a/c

Will this be the same harness so I can do my swap wiring ahead of time or do I need to find another harness? And I just need the engine harness right not the body harness?

Umm... you'll need the plugs for the a/c system, basically the wires turn on the pump and a/c idle switches and such. If it's gonna be a temporary thing, you can also wire up the a/c to an alternate power source and run it off a switch, but it'll affect your idle (no biggie tho)... The interior stuff such as power windows and such shouldn't be affected.