Ok noob question, but what is the cable that plugs into the side of the 901 tranny that is right next to the shifter connector on the left side of the tranny?

Never noticed it before until doing a close inspection of my starter. Looking at parts diagrams but can't find it.

Reverse light switch. There should be two wires in the same 'bundle' as the yellow wire on the starter. Those two wires plug in there to make your reverse lights function.

Yes, that makes sense. And it does run with the yellow cable.

Thanks!