A better question would be how bad is the bad cylinder. If we're talking about small rust pits I'd say live with them. I've done it with no noticeable effects.

Also it is quite unnecessary to take the entire block out to 60 over if it only needs one hole to be that big. We're not building Formula One engines here, or Pro Stock. The casting quality of Mopar blocks is such that one hole may be quite satisfactory at 60 but others may not.

Don't remove more metal than you have to.

I know that pistons usually come in sets but singles can usually be had for off-the-shelf items. For example, Sealed Power pistons become singletons if there is a W in front of the part number. A set, H843CP becomes a single piston numbered WH843CP.

But the first thing to determine is whether you can live with the cylinder at 40 over.

R.