RE: Transmission Question(s)
IMO, first off the gear-flip and FOC is a waste of time. I started out with a gear-flipped Aftershock tranny, and didn't notice that much difference.. I was never impressed with it. Then I started having all the issues too.
Then, with all my issues - which, btw are EXAXTLY as described above with the audible CLICK into gear, etc.., I was always messing with and cleaning the 2-speed, and nothing ever seemed to help.. In the end I just gave up on running smaller truggy tires. In the same truck with truggy tires the tranny(XXL) and 2-speed and even the clutch were all brand new, and it still slipped. Put on some HPI Terra Pins - problem gone..
As for your problem mechanike, do what he said.. Sounds like he knows. I never did all the sanding and stuff - but frankly I don't think you should have to. And again, big tires on, everything works perfectly.. Unfortunately.. I really would like to have my second LST2 as a track-truck to run with my buggy...