Purchased a package of #6 star lock washers for the switch screws which came without any lock washers.
Shortened a screwdriver tip for use in my 6mm hex ratchet so I could tighten the switch screws in the narrow space between the switches and the breakers. Also made use of a small steel angle bracket out of the scrap box to use for tightening the screws on the governor and MFS switch which have even less clearance. I obviously didn't consider contact location when shopping for switches.
Installed the jumper wires and final tightened the screws.