We got the bands adjusted by finger tightening all four bolts a few turns. These now feel like they can not tighten any more due to the U-channel bolt keepers.
Our initial testing by pushing the Max a few feet forward/backward shows the machine now has brake effect on both sides, forward and backwards. Neutral on both sides is fine, as well.
We expect to be done putting it all back together tomorrow and test drive it. I'll report our results here.