71C rebuild questions

Rebuilding a 71C from a 86NA for transplant into my 86T over the next week. Just a few questions:

- Does anyone know what the neutral switch on the T5 actually does? Not the clutch pedal switch, but the switch actually in the transmission? I know my clutch pedal switch works since it disengages cruise, but what does the neutral switch add further? I found this thread, but it didn't seem to arrive at an answer: http://z31performance.com/showthread…neutral+switch

- What, if anything, are those of you who have rebuilt transmissions using for snap rings and shims? There are a few key points where the FSM calls for checking clearances and then selecting an appropriate shim or snap ring. I rebuilt a 4-speed on my 71 240Z and didn't check clearances, and it worked great and survived a high-compression bored-out 280Z engine swap. Any experience either way?

- I also snagged the driveshaft and transmission mount. I think this should cover any differences?

- Any other snags or gotchas to be prepared for?