Ebay was the first place to check. As far so I know the 1982 and above Dohc reg/rec are not compatible.
The following years and models are compatible.
1976 RD400C ELECTRICAL
1976 XS360C ELECTRICAL 2
1976 XS500C ELECTRICAL 2
1977 RD400D ELECTRICAL
1977 XS360D ELECTRICAL 2
1977 XS360_2D...