is there a difference between fox cougars and tbirds power steering pumps assembly compared to fox mustangs?
you know I think this is another one of those questions where it depends on who you ask. IMHO a pump is a pump. I have been running a pump for my 79 cougar with a steering box on my 88 TC with rack and pinion with no problems at all. so to answer your question they are the same.
I ran a pump for a crown vic for about 2 years, and I have ran at least one car with a mustang setup for a while.
Just about every ford car(RWD, more than four cylinders) seems to have the exact same PS pump. The only thing that changes is the blowoff pressure and flow, which is controlled by a plug that fits between the pump and the high pressure line. I am using a pump and plug from an '02 Mustang, and it seems to work exactly the same as the old one.(Which is good, because I really enjoy my steering.)