Car no start

[Slow Joe]

My car is a 1986 300E. It wouldn't start one day so I tested the starter and the solenoid was dead. I got a used starter from the local pnp. I bench tested and it worked fine. Installed it and it turned over fine. Shut if off and pulled the key. All of the dash lights stayed on. Now it won't turn over at all and the dash lights wont go off. Help!
Any ideas? I checked all the fuses and they are fine.