i'm going to put a set on my m motor but the ford racing one's are too exspensive for me..i'm going with the scorpion set (half the price)...check out ebay..Item number: 7955288908..
Scorpion roller rockers PEDESTAL MOUNT for FORD 351C, 351M, 400, 429, and 460 engines.SCP 1024 1.73 ratio PEDESTAL MOUNT

or 7914879405
Size 7/16" pedestal mount, and 1.73" ratio. Fits all 351C 351M 400 429 460
Improves horsepower and reduces friction

Does not require guide plates, hardened push rods or pedestal machining. Includes pedestal inserts & bolts.

sounds like the hot ticket..
not sure about the improves performance but i'm sure it reduces friction