The Stovebolt Site Forums The Shop Area The Electrical Bay 1970 GMC 1/2 ton wiring mystery

Ok, I'm starting my latest project. It has a 307, 3 speed on the tree. I haven't been able to locate a schematic that addresses this item. Previous owner(s) have cobbled up some wiring over the years and left some dangling. Specifically I'm looking at what appears to be a second temp. sensor in the the right hand head with a green wire that goes to a relay on the firewall. The relay has a pink wire that goes to an always hot terminal on the fuse panel. There is a blue wire on it also. I also have black wire coming out of the trasnsmission, not plugged into it, literally goes in through a hole in the transmission and I can push and pull it about. ???? In my searches I'm finding similar schematics that show a transmission relay switch and a second temp switch with a time delay relay all being used for spark control???