MerCruiser 4cyl 470 170 170hp 3.7L Rocker Valve Cover 41638A1 41637 1983-1986 Trim Parts note that these are for

note that these are for V8 models because of the installed opposing water outlets

13 (once you install the proper #206 XHS hub kit)

981556 / 0982062 / 0982597 / 982695

Lower Gearcase Driveshaft Found on OMC Stringer Stern Drive V6 & V8 Models 1978-1985 (Mechanical Shift & Hydro-Mechanical Shift Units)

​​​​​​​Seemingly there are multiple part numbers of motors that this is mentioned

MerCruiser 4cyl 470 170 170hp 3.7L Rocker Valve Cover 41638A1 41637 1983-1986 Trim Parts note that these are forItem Details Removed from a 1983 1984 MerCruiser "470" (170hp) 3. 7L 4cyl 2BBL (SN 6890474) Overall Good Condition, original paint Parts Included MerCruiser Cylinder Head Valve Rocker Cover 41638A1 (Stamped 41637) This particular one was only used on 2bbl models as well as the 4bbl models with the 98348 C1 intake manifolds as these had the provision on the top for a stud for the 4BBL carburetors The 488 models had a different valve cover, but could be