I had noticed an alignment issue with using the Mato gearboxes on an aluminum plate. I also wated to use some 400 size motors but the length wouldn't allow me to use them without some modification. So, to solve these issues I decided to remove the mount lugs from the chassis and replace them with "Plastruct" Styrene. This stuff is great to work with. It can be cut, sanded, drilled bent with a little hot water and glues easily with Cyanoacrylate adhesives.
first i made some stanchions to elevate the mounting plate for the port side box by gluing several layers of different thicknesses of Styrene together then using my Dremel I even up the layers like the ones in the first pic some before and some after.
next I cut a plate to mount the motor to and drilled pilot holes for the screws.
Then I made two stanchions with enough angle on them so that my Permax 400 size motor cans would clear each other. I attached them on their edge and glued a gusset between them to make them a bite more rigid. I also have the two mounts attached together for strength.
Finally is a picture of the gearboxes attached with the 400 sizes motors installed.
