Bought a used 86 325. During some recent work, the battery was unhooked and the radio reset itself to "code". The code given to me by the dealer does not work. Am I missing something??? Do I just punch in the code after turning on the radio or is there a double-secret sequence of events that has to take place here? Also, in case the code is invalid, where would I get the correct one??? Aaaaagggghhh!!!