Mine is a 1980s MIJ Jag, 62 reissue I think?? Never was quite sure, got it used almost 20 years ago.
I've tried to keep mine as original as possible. I had to replace the tremolo bushing assembly as the original one was split in two places (whoever had this thing beat the crap out of it apparently).
Few years back had to get the tone wheel replaced (old roommate didn't want to stop turning when the knob stopped).
Put new pickup covers on it.
New trem bar. Had to sand the post a bit, but it works well now.
Replaced stripped screws.
Thinking about replacing the bridge, as the stock bridge is pretty corroded.
Original owner soldered the saddles together (?!) and I thought I'd have to replace but knocked the solder loose pretty easily.
I get my parts from Angela Instruments, as they carry all authentic Fender replacement parts for Jags, just to keep the "refurbish" as original as possible.