When securing the motor mount and layshaft bulkhead to the chassis screw in using the X pattern being 1,4 2,3. Do the same when securing the top deck to these parts. Also the optional chamfered motor mount and chamfered layshaft bulkhead have machined pockets, thus lots of right angles etc, which creates a much more rigid and stronger part as well as being lighter. When installed square the layshaft should have a little side to side movement.