I've got a VZR gearbox here and a previous owner (as opposed to the person who sold it to me) recently informed me of some issues with the gearbox that I'm hoping to attend to before I use or more likely sell it. The first issue is minor; stripped threads on some of the bolt holes in the casing. The current plan is to drill those out, helicoil to suit the regular bolts and move on.

The second issue is a bit more serious. While the box is still usable, I've been told that it would crunch a bit on a fast 5-4 downshift and would pull to the left a bit while coasting. The gearbox has been disassembled and reassembled in the past, with the most recent work being done by a workshop that doesn't seem to have had much experience with gearboxes. At the moment, I'm planning on pulling the case apart and checking it all out and would like some suggestions on what to look for.

I've priced up a few of the bearings and seals and what not, but having a bit of targeted parts hunting would make life easier (and cheaper). Any advice or guidance I can get here would be very much appreciated.