[New_Guy_46]

I went to test the fuel lines today and the number 6 fuse keeps blowing. Narrowed it down to the black and yellow wire and a white wire. The white wire is the fuel solenoid cutoff but the other end on the fuel solid cut off is purple. The black and yellow wire looks to be power for the reverse/seat belt switch. Does anyone know where this switch is?

 

[spiderserie4]

reverse switch is inside the bell housing (yes, clever people they were....not!) that has a yellow/black and a white wire.
Check the wires coming from the bellhousing, they are clamped to the side of the trans. perhaps wires are grounding out there?

this is an older tranny, but same thing

seat belt switch....? you mean that infamous seatbelt interlock...that was only on MY74 then quickly done away with, I thought, so I doubt your 73 has that (thankfully)
Or do you mean the pair of white buzzers, seat belt buzzer and key/door open buzzer? They should be on the steering column right side, but they have red/black wires and a pink and a white.