'66 Chevy 250 Inline 6 Build

Hello to all. I am new here and I am needing some information. I am putting together a 250 6 cylinder for a '69 C10. This will be a daily driver but with some goodies. I am planning on a .30 bore, ported and polished head, headers, and 4 bbl intake for either the Holley or Edelbrock. A nice lumpy cam with new springs, valves, rockers, etc. MSD billet dist. I am having issues trying to decide which piston route to take. I would like to bump the compression up to about 9 or 9.5 and I would like to use flat tops to accomplish this. But I have been told that using the OEM dished pistons and shaving the head .0060 would be the best route to preserve the swirling of the dished pistons. ??? Any ideas? Opinions? I am also contemplating putting larger valves in but I am not sure if what would be gained would justify the cost and benefits. I am having the rotating assembly balanced once the piston issue is resolved. I have a new Centerforce II pressure plate, billet steel flywheel, clutch, etc. Currently I am planning on going back with the original 4 speed granny, but I am also contemplating a 4 speed for some mileage benefits. Any ideas, carb, pistons, head work, etc. would be greatly appreceiated. Thanks!

I just purchased a Clifford Intake for inline 6's off Ebay. It fits 194, 230, and 250 engines without integral head. I was going to install it on my 194 six but I'm having second thoughts. If you're interested in buying it let me know or else it will probably go back on Ebay.

Sgt Steve