Ah... I was just basing that off the number that I was printed on the side of the cylinder block. I'll update that in my profile.I just noticed that you have it listed as a CX500E. The CX500E (AKA Eurosport or CX500 Sports) (pic below) was only made for the '81 & '82 model years and wasn't sold in North America. they have completely different bodywork and "boomerang" Comstar wheels.
I think the confusion may come from the engine serial number beginning with "CX500E-". I don't know what Honda's engine numbers were supposed to mean but AFAIK the actual CX500E bikes have engine numbers beginning with "PC01E-".
I believe the '78 model was just called CX500 and is sometimes referred to as "standard" to differentiate from the later CX500C (Custom) and CX500D (Deluxe) models.
I do wish the E model had been sold in the states, or at very least been offered with the dual front disc as standard from the beginning.