Harley-Davidson Tachometer Lamp FX Shovelhead 1978-L (OEM/NOS 92046-78)
Factory references show FX use (all models except FXWG) beginning in 1978 and used to at least '84. We did not this part number in any other Factory reference, so it would appear to be exclusive to the FX Shovelhead models, only.
050721 B-2 (OS)