Well, How many miles are on the engine and when was the last rebuild if any?
Dan, IMVHO, If the motor was never apart, and there's a ton of mileage, its time to pull it out.
Again IMVHO, If it was never touched your only looking for more and more trouble.
Tank the block, massage the cylinders with new rings and pistons, modern gaskets.
I think you understand that those studs go all the way through the block.
Just my 2 cents , do it once , do it right and in your lifetime you will never go back in again.
GTJOEY1314
