Daily driver 75 360 .060 over

Cylinder thickness has little to none to do with overheating. That's a chebbie thing that came from the 400 small block because it does not have water jackets between the cylinders. It's a myth with anything that has water between the cylinders. It all has to do with how efficient the cooling system is. If you get all the right parts in place, you'll not have a problem.