I put a Clifford Alarm in mine when I did the 5.0 swap, and in a few other Fords. Its easy if you have alarm instructions and mustang wiring diagrams. Still works 15 years later, but the Key Fobs buttons are a little worn out and I can't get the replacements to program.
maybe i will get it done professionally, im wondering if theres gonna be issues because it used to be a 2.3 liter svo turbo engine and now has a 92 fuel injected 5.0 in it. not sure if that would change anything im guessing so.
Get the wiring diagram for the set up you are running. I just installed an alarm/keyless entry/remote start in my 89 and it was pretty easy. I also have pretty good knowledge of wiring.