More welding on the upper case.
I also refurbed the left control switch. This switch is one I got off eBay for a later model (the '68 switches are very hard to find), so I didn't want to put too much effort into it, since I'll be replacing it with the proper ones at some point.
I disassembled the whole switch and cleaned up the contacts and the housing. The wiring all looked good, so I didn't mess with that at all. A couple of hours in the tumbler, some soap and water, and then a light buffing is good enough for me.