M117.xxx Heads.
 

I have a pair of heads from a 75 117.983 engine.

Are they the same as heads from a .986 engine? aside from the obvious camshaft attachments and oil tubes..ect.

No. The heads themselves will not have the passages for the hydraulic lifter system so they need to be used with manual-adjust cams & ball studs. You can put them on a 986 but only when used with the cams & studs appropriate for the manual ball studs.