1990: All Models for Filter To Pump line
Drain Screw: 10-49956 (Standard Pre-1996 Threads)
0L Camshaft Assembly It's probably C3AZ-6250-V or possibly D3OZ-6250-A (I think this number was actually for the one in the 190hp)
Appears to be generally used on GM V6 Vortec engines 1997-2007 (So possibly some MerCruiser models as well)
which eventually was what was converted to a thermostat housing) used on various early MerCruiser Models outlined below:
Johnson Evinrude Outboard Carb Intake Reed Plate Valve 40hp RDSL-22 1960 378012 OMC Propellers 1990: All Models for FilterItem Details This was removed from a 1960 Johnson 40hp Outboard RDSL 22 C Sea Horse 2 Stroke 2 cylinder Serial # 2136474 Notable Part Number(s) Leaf Reed Plate 377202, 0377202, 380243, 0380243, 305361, 0305361, 311363, 0311363 Leaf Stop 304709, 0304709 Leaf Valve 304708, 0304708, 308938, 0308938 Intake Plate 378298, 0378298 378012 Link Bar: 309241, 0309241 Throttle lever and Pin: 378985, 0378985, 376478, 0376478 Spring: 303296, 0303296, 307408,