Just a few thoughts.
All coupes have this retractor, too, such as the W126 chassis 380SEC / 500SEC / 560SEC and the W124 chassis 300CE / E320 coupe.
Someone should be able to help you with this problem.
For your inoperable brake lamp, did you try cleaning the slot that the bulb slides into?
There must be something wrong with the power antena motor. You might try replacing the antena and the motor. I see them on Ebay all the time.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".