[Hurlbird]

1969 XF 428 (370HP) in 68 ram air Firebird. Car has AC which I want to keep. Tremic 5 speed with 373 rear end. Running all stock parts including 68 long branch manifolds and Quadrajet.
It runs great right now on pump gas, but is leaking rear main oil and the head freeze plugs are leaking. The motor appears to be untouched. Does not burn oil. I want to freshen it up so I can literally drive this anywhere and enjoy performance and reliability. I’m worried about 50+ year old internals. That said here are some questions I have:
1. Why does it run so well now with pump gas? Most likely due to ring wear or another cause creating less than stock compression? No pinging or run on.
2. Should I check compression to determine ring wear? Or could I be fooled by valve wear?
3. Do I pull heads and look for ring ridge as the best indicator for rebuilding the shortblock?
4. I understand I want to run about 9.5:1 compression for pump gas. How best to accomplish that? Different pistons? Different heads? Both?
5. Is it more effective to purchase after market heads or do I rebuild the #62 heads I already have?
6. Aftermarket heads designed for stock brackets including AC?
7. If I want great performance but lower compression, how do I accomplish that? Focus on heads/exhaust? I want to keep LB manifolds.
8. I don’t beat it. Do I just rebuild/replace the heads/ perhaps a 068 cam/timing chain and other wear parts, and not worry about the short block? See #1 worry.
9. If I’m doing the rear main seal do I do the short block since I’m there already?
Thanks for ideas! -John