[Superman]

Wrist pins can be stubborn, so I suggest using heat. They are MUCH easier to remove from a warm piston than a cold one. Once the P&C's are removed, then you'll have access to the stud area. Hopefully they are all long enough to get a pair of pliers on. Use oxy-acetylene. Trust me on this one. Rent a unit if you have to, but don't mess around with flame that's not hot enough. After perhaps a minute of heating, they will come out. Keep heat on them and turn smoothly until it's out.

As much as I hate to say this, you might want to use the current-generation of Dilivar studs to replace. Your engine makes more heat than mine, and those Dilivar studs may be a good application for your engine. Maybe someone understands this better than I.