I recently switched over to Matrix II’s with Boardnamics M1 AT gear drives. I have MBS 5stars and 200x75mm pneumatics. In order for the tires not to rub the gear drive casing,I used spacers to push the wheels out a bit. However, when I do this, the hub partially sits over the threaded portion of the axle, making the wheel wobbly and unstable.
Etoxx has truck extenders, but it looks like they are out of stock.
Have you tried DM’ing or emailing @NoWind? I don’t know what he’s up to these days, but he might have an extra set or just make them on request. I think he’s still basically a one man (death metal ) band, so you might just need to rattle his cage.
I’ve got matrix 2 trucks with an etoxx gear drive and I need some extenders. @NoWind do you still have any available? I have a friend that has the same setup so also needs some. We live in Australia, would you ship over here?