Nice job on the grub screw!
Did you change the o-ring on the output shaft? I guarantee it's dried out and is going to leak one of these days, and if you have even a tiny bit of bad karma, that oil is going straight for the clutch friction disc.
On the gear position switch, chip out all of the old broken up potting compound, be fussy and get every little bit out, then wash well with brake cleaner.
After it's good and dry, mix up enough epoxy(don't use the quick stuff, you want it to flow into all the spaces) to fill the end where the potting was. Work the epoxy into all the nooks and under the wires with a toothpick. Be careful not to get a lot of air bubbles.Let it sit until it's fully cured. Tip: Clamp the switch body in vise grips to keep it from flopping around while you fill with epoxy.
After the epoxy has fully cured, take the switch apart(carefully! there's some small springs and other easily lost stuff that wants to escape). Clean all the metal surfaces and bits in a rubbing alcohol soak, dry for a day and shoot everything with Deoxit. Then you can put it all back together.
When you install the gear position switch use allen screws. They are a lot easier to turn than the hex heads that are there now. A new gasket will help keep the crap out.