Group's advise thus far: (1) determine true cause of stud failure - Either heat or corroision or pre-load issues would likely indicate changing the full set. 

                                    (2) Always replace the stud cap nuts - the nut you torque to "set head gasket"....WHY always replace?  The studs have visible corrison.

                                    (3) Piston rings really do not wear - they loose tension, break, get stuck etc.

                                    (4) Piston wear is most likely to occur in the ring lands on the pistons. 

                                    (5) If you're replacing the rings you probably should hone cylinders trying to avoid piston slap - Can anyone explain this further?                                                    (6) New rings will set within old cylinder jugs, even without honing  - Can anyone attest to this fact(s)? Tells of what you did?

                                    (7) Takes time to properly hone cylinders, else better off adding a new set of cylinders - at that point you should do both sides of engine.

Is there a trick to (a) removing the wrist pins that hold pistons to rod in this Vanagon engine - I've done aircooled engine but never Vanagon's?

                            (b) re-installing the new ring set (3 rings in my case) onto the old pistons

                                    -Art of inspecting and clean the ring lands on the piston - PLEASE ADVISE!

Sorry to "scream" but I really don't want to get this wrong - Thanks in advance for group's collective wisdom, I'm always impressed....

Have a good day!

Larry Word
Ga.