I thought that there was a fix that came out in the later 70's-80's that had something to do with the oil pressure sender. Don't think that oil temp sender was common back then or maybe it was a TEE fitting with pressure and temp. Supposed to give more precise temp signal to the electric choke as per what the factory was using during that time line. The electric choke was an upgrade from the intake manifold well/bi-metal coil, but this hybrid was supposed to be right on with opening the choke at correct motor temp.