[1969GPSJ]

Just exploring options here. I have a 1969 GP that is my resto-mod project. I am trying to maintain at least the sense of originality while still adding comfort and performance improvements. I have a used (not working at this time) '69 or '70 GP AM/FM radio. I could get it repaired and updated with a bluetooth module. Or I could get an aftermarket sound system - some (like OPGI and Ames) list radios verified to fit the GP dash. There are other companies that sell updated sound systems that fit the Lemans GTO, but they do not list these systems as fitting in the GP. Is there any reason why a radio that fits in the A bodys cannot fit in the GP? I can't realistically see any, but I'm just not sure. Ideas? Thanks!