Also check out Patricks in AZ. He is really good on Chevy sixes.
I bored my 235, decked the head, installed stellite seats, replaced the springs, valve, etc. and upped the compression to 8.5:1. Then added Offy intake and dual Holley 2bbls and a Howards cam. Oh yes, also did a HEI ignition and a Fenton manifold. 235's can be bored up .100 +. So yeah, I'd say you can do a few things with your old six and remember this....NOTHING sounds better than a hopped up inline Chevy six. NOTHING!
www.patricksantiquecars.com