"Matt:
I looked over the 78
"Matt:
I looked over the 7800 as it was closest number I could find...a long day for me. If the wires go to a "box" on the shaft, I'd guess it to be the neutral safety switch.
Get an ohm meter (or a self powered test light)and hook it between those brown leads. If it shows continuity in neutral and an open circuit in FWD and REV, that's what it is.
Going on the neutral safety switch assumption, the manual should be fairly clear on how to hook it up. How to actually do it, I think, would be based on whether this is a replacement or an upgrade. The end result, electrically, should be the same."