In 1972 I bought a .060 over 65 GTO 389 that I owned for a whole week before the cylinder wall collapsed into the water jacket. I had bought the car mostly because the guy needed money, and had all the receipts for the engine parts and labor.
The engine stalled when the cylinder collapsed dumping coolant into the #3 cylinder. That hydrauliced it, so I popped the clutch out while I was still moving, ignorant of what had happened inside of the engine. The crank broke in 5 pieces, one for each main bearing, the engine was completely destroyed internally. 4 pistons weren't broken, the cam surprisingly didn't get nicked, and the cylinder heads survived. Everything else was scrap metal.
After it happened I pulled over to the side of the road and tried to crank it with the starter, it was locked up. Further investigation shows oil, and coolant running out of a gapping hole in the pan, and block.......
I had another stock 389 2 bbl engine from a 65 Catalina that went into it so I could get back and forth to work that went in that weekend. We then did a post mortem on the blown engine.
Expensive lesson learned about 65, and 66, 389s, with thin wall castings, they don't like to be bored .060 over, 64 and earlier, usually have enough meat to go .060 over. 64 is also the only thick wall casting that has a provision for block mounted starter though. After that debacle I was pretty much going for 67, and later blocks for all my builds.
Some 65-66 389s were okay for .060 over, but some weren't, and this was before sonic testing was common, so I just avoided those blocks. A standard bore 400 will accept your .060 pistons, but it would be a challenge to find one with minimal taper after decades of use.