Starter help - 77 R107 450 SL

I am befuddled with my starter issue. I have a new starter that I bench tested with existing my battery. It worked fine which is expected with a new starter/solinoid. I attached the car's wires to the new starter but did not fasten to the engine/flywheel. Tested with a voltage tester, I have power to the starter and solinoid when the key is turned. Power to solinoid is off when key is turned off. I go to turn the ignition on and nothing. I first thought since the starter is not touching the engine, it wouldn't have a ground. So I connected a ground jumper from the engine frame ground to the starter. Still nothing. Relay is turning on (clicking) when I turn the key. I even replaced the ignition switch as I thought that no could have been the issue. Unscrewed that and turned the ignition switch with a flat head screwdriver and still nothing. I even used a jumper wire from battery positive wire to starter positive post and it turns on so I know the starter works but not with the car wiring. But that is completely bypassing the solinoid. Any help would be greatly appreciated.

Update : I switched the relay with another relay with the same rating. Same problem.