ax-5? I'm getting mine rebuilt right now, parts will be at least 130, labor I don't know. I'm going tomorrow for an estimate. I would have rather done an ax-15 swap, but my dad is having the '5 rebuilt as my christmas present.
You need at least a good clean room and a good hydraulic press. Make sure everything is marked and placed on a clean table in order of which comes out/off first to last. Replace parts that are no good (synchros and bearings most likely), then put back together in opposite order. Torque to specs, fill up with oil, and put it back in!
I have no practical knowledge, just read and watched lots of instructions.