PCM predicament

I have an 88 country squire, engine is from an 88 mustang H.O. (refurbished) with a cobra cam. Tubular GT-40 intake and 65mm TB. Opened exhaust to 2 1/2 dual. I was just made aware of the mass airflow sensor need and conversions. I’m having trouble finding out what PCM I need, and where to get it. Can anyone point me in the right direction? Maybe it is more simple then I’m making it, I’m lost and kind of confused. I believe LMR and BBK have all I need, except this PCM.