[Al Skierkiewicz]

Jeff,
An arrangement that will work for the whole season is to make a sub-chassis that the drive motor(s) mounts on. You can use a slot arrangement to mount this to the main chassis. The simple addition of a bolt and locknut (the bolt is mounted so as to pull back on the motor mount) arrangement will allow you to tension the sub-chassis as the chain stretches (break in). You loosen the mounting hardware, take up the slack with the tension bolt and then tighten the mounting hardware to hold everything in place. Use bushings to support all shafts that the chain engages. The bushings are available from Small parts and are worth the money to insure smooth running. Use the shaft collars to hold the shafts in place against the bushings and add a little oil every once in a while to keep everything moving.