I have a bunch of loose parts from at least two engines.  The rod part number is ECZ6205A.  I think they may be from a 56 Merc. 312...but I'm not sure.  Are these the same as the 57 C1TE6200's?   Three of 8 of these with pistons attached are sort of frozen on the rods.  I sprayed WD40 on the piston pins and got 1 separated.  Are piston pins usually replaced in an overhaul or reused?  Is anything done with the piston end of the rod?  Are the bronze bushings pressed out and replaced, resurfaced or reused? 

Paul J. - '57 E Code