This is more of an FYI post. Apparently Honda made two different versions of this factory radio. My 91' Prelude Si ALB model is the deck in the bottom of the pictures. Where they differ is one model (39100-SM4-A210-M1) only has one antenna port where as my original factory radio (model 39100-SF1-A200-M1) has two antennas. The only visual difference between the two is my factory radio has 2300 labeled on the lens where the other model has 1100. I was under the impression that all 3rd gens had two antennas, the power antenna and the antenna built into the rear window. My question, is there a 3rd gen that only came with one antenna?