After looking at the engine codes you have listed I could not find the applacation for my engine block numbers. It is a YE 348706 The heads are 143. I did find some posts and info on the heads but not the block ID. This is not the motor or heads that came with the car. How well do these match up for a decent daily driver? I had them rebuilt several years ago and have very few miles on it so far. Put a elderbrock 4brl carb and intake on it. Cam is a Speed Pro Sealed Power CS 1022R. Any and all info would be nice. Also put a turbo 400 tranny in. 355 posi with Hotchkis multileaf rear springs. In paint shop now and interior will be done as soon as I get it back. Will be nice to get it back on the road after many years of slow going. (1967 Firebird coupe)