Unless you're going for a really high rod/stroke ratio like a 351W with 6.58 rods to get a 1.88, which is a good torque motor but probably wouldn't match up with that potent of a 393 you're talking about, you probably want the bigger cubes of the 393. The small difference in rod/stroke with the 377 etc is too small to make up the diff in the cubes. The 351 block should handle that, but might be good insurance to use ARP studs etc. Keeping the r's around 6500 is a wise idea (stress on the lower end goes up WAY fast with higher revs), and should match the effective peaks of hp & torque for that cam with that many cubes. In fact, your torque peak will probably be around 4000+ and hp peak around 5000+. In fact, I think Ford uses a bigger Comp cam in their 393 crate motor. You probably also want to think about Eagle or other reasonably priced aftermarket rods. Using a dished piston, like JE's Yates style, will also yield more torque (keeps the combustion pressure more on the piston as opposed to the head/cyl wall surfaces as well as resisting detonation better). BTW check
www.oemfordparts.com for a Ford stroker kit with hd truck rods, or crank by itself or whatever. for good discounts on ford parts check
www.fordpartsnetwork.com