Some more information...
ALL of the off-the-shelf 351C the FORGED stroker cranks (Scat, Eagle, etc) require EITHER of the following:
1. Crankshaft spacer ring (CAD drawing to be provided once I verify fitment tonight)
2. Rollmaster timing set CS3130 - about $130, but no spacer ring is needed with this timing set
The Scat 9000 series 351C stroker crank is a correct Cleveland crank but it's CAST, not forged.
Ford Motorsport provided the spec to Scat to manufacture the forged 351C cranks with the Windsor snout to be compatible with the SVO blocks, which do not require the spacer.
Scat supplies Ford with the cranks used in Ford Motorsport's stroker crate engines.
The Scat forged crank (and possibly others) does not use a std Ford woodruff key in the crank snout. The key slots are sized for small block Chevy Woodruff keys. I will verify measurements and fitment this weekend.