The shifter in my 04 has a lot of free play, and today I finally got the car running, but when you put it in first, it would actually start in 3rd, and it was spark knocking like like crazy. Well I figured out why.

When you pull over to 1/2, my shifter ball moves up because the retainer is broken. But if you push down you can get in the right gate.

Has anyone else had this issue? And do you know the part numbers?

I fixed my '01 Z24 with a big O ring from Ace Hardware and lots of Super Lube silicone grease.
Works like new (not that I know how that would be cause I bought the car at 121K).
Bottom line, it shifts easily and accurately !