Can any of you trans experts give me a bit of advice? I just purchased a well used ACN code five speed 020 to replace the GC four speed in my Rabbit. It spins nicely and has no signs of leaking, but when I pulled the fifth gear cover to replace the TO bearing, I noticed the pinion shaft has been contacting the inside of this cover enough to leave a decent detent.

Is this normal wear or catastrophic? I will eventually have the trans rebuilt, but I'd like to use it for a few months before I do. Any advice?
Thanks, Derek