The OEM VR uses an electromechanical system and the solid state uses resistors and diodes (something like that?)....they are supposed to function the same. Matter of fact, my rig had a solid state VR when I got it. Drove it that way for a while till I started in earnest of a minor...
@cruiserboy14 - An OEM 1977 regulator.
Installed:
Backup:
Solid State option with updated connectors from @ToyotaMatt :
I don't mind parting with one of the solid state units. If you need one, send me a PM.