1969 Oldsmobile Cutlass need to know the wiring for the sol

Electrical problem
1969 Oldsmobile Cutlass V8 Two Wheel Drive Automatic

i have a electrical issue with my 69 olds, not sure where the wires go from the solenoid, on the solenoid there is a "R" and a "S" ....i think the S goes to the Starter Relay, and the R goes to the COIL????

which ever one goes to the coil...is it the POSITIVE side of the coil also??

i have a grouind wire from my batter to the frame and its MELTING????


i did replace the horn relay and i am waiting for the starter relay (behind the brake booster)....

i also replace the voltage regulater....(could this be damaged due to the problems i llisted also???


thanks
Steve