Transmission wiring

[paul mora]

I need help I am wiring the tranny and I was told i need to install a relay downstream of the neutral safety switch on the tranny. The photo shows the pins and where the wires connect to based on a,b,c,...... first question is do I need the relay and if anyone could simplify
A not used
B
C. Fused hot wire on or off when cranking
D. Ground
E to relay this trips relay
F back up or reverse light
G

If anyone can answer my relay question and fill in the blanks and tell me how to wire this I might get it running.