Custom Camper factory solenoid?

[PushnFords]

I just bought a '72 C20 Custom Camper with the 400/402. On the driver's side inner fender right by the P/S reservoir is a Ford style starter solenoid. One wire goes across the radiator support to the battery, one is coiled around the solenoid, and one goes to a little metal relay screwed to the rad support at driver's left lower corner of the radiator. I don't want to rip that stuff out & toss it if it might be factory.....