I have decided to keep the 273 commando very close to stock. I am keeping the carter afb 4 barrel and the stock cam. I replaced the heads with a used set adding new valves. The gasket set was from felpro. The head gaskets were very thin metal. I did some cleaning on the exhaust but not a lot more than that.
Pistons were replaced with an original set of dome pistons and new rings and bearings throughout. As far as compression I haven't given it much thought. It was 10.5 to 1 factory but I'm not going to guess what it is now