Just thought about something: Instead of making a new cap, you might get by using a scrap connecting rod from a heavy duty engine (I'm sure someone here has a pile of them laying around). Whack off the small end and weld the big end to the end of your rod. Might have to insert a custom bushing to compensate for the mis-matching diameters but may be easier than trying to remove a stuck pin. Again, just looking at this through the eyes of a machinist....