A little advise

You definitely want to do the valve reliefs in the bore to help them breathe. Strong running engines and if you do a little research you can find that getting rods with the 0.990 pin will open up piston choices! Some high compression Pontiac pistons could fill the bill..... especially if you make it a stroker or go with longer rods. Check out some of the rods and pistons available. If it runs good as is I'd drop it in with a cam swap of course. Some have the truck-industrial heads on them also which would need to be swapped out for 452 or 906 etc...