Look at it as a challange which is part of the fun. If you are so inclined, take the motor apart. Should not take you more then half a day. Take photos and keep the parts organized. Get it down to a bare block. Get the block to a reasonably decent machine shop, tell them what is going on and have them throughly mag the block. If it passes mag, and it might, have them check the decks and make sure they are flat. If not, have them cut a bit and put the motor back together. A caddy motor of all things. How cool!
X2.
A Caddy motor in an old truck, that was modded that way 60 years ago by your grandfather….is a novelty worth recreating.
It will be the opposite of convenient or easy. But the result will be worth the pain, IMO.
