I have a knackered jap 5spd

[Tj.]

It actually belongs to my old man, and I'm also not too sure what's wrong with it.

Quite obviously I'm not looking for a how to, just an idea on how hard these things are to fix.
According to the old fella the bearings are a bit slack and it jumps out of some gears.

Is it a case of opening it up and finding and replacing worn parts or is it too much stuffing about for a newb to fix?

[panda]

A lot easier just to replace the entire box with a second-hand one from the wreckers. A lot of late model Sigma's used them.

[Tj.]

Gotcha.

If you don't ask you don't know.