I bought new in 1990 a 35th aniversary 5spd. It stickered a little over 20K. I also later on had an 89 Cougar XR7 5spd. Popped the HG's on the Cougar. Fixed that, then a year or so later threw a rod, probably from the HG's going(hydrolocked at some point). Put a new motor in it than moved on. They are extremely difficult to work on, and though they drive great don't make the power of more modern vehicles.
The 89 with CAI, adjustable fuel pressure reg, ASP upper pulley only went 14.3 @ 95.