RE: engine rebuild
My mistake I miss read your post ,After looking at the breakdown of the engine it appears to be a ABC design so Sport is correct what your feeling is the pinch just before TDC .But here again if theres not enough compression the engine will not run .
Was these parts new or used that you bought? After reading what you said about wear it appears they was used,as a rule not such a good idea.
Mecoaengines.com has the complete line of parts for that engine new and in stock .
Good luck .