55,
I left you a message in the other forum. I'm not convinced that the relay is the problem.
Try this first. With everything hooked up -
Connect a jumper wire to the KD terminal of the relay to ground, if the solenoid clicks, the relay and solenoid circuits are OK. If no click or blows fuse the problem is usually the solenoid. If it turns out to be a relay problem, the original stuff is hard to come by and has become expensive. I usually install a Bosch type relay on the OD's that I do for customers. They are available at Napa and others for about $25. It will require some minor wiring changes but I can help you with that.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine