I want to put thunderheaders 2 into 1 on. The only bike they doesn't seem to fit is my 04 Police Electra. Am I missing something, is there something different on the police version that makes it so different from the standard? They list 04 Electras and 05 police Electras ???? Also, want to put Arlen Ness "Big Sucker" air filter on, any thoughts.