[blykins]

Sure, but a Windsor is almost 3/8" taller in the decks.

With a factory bore Windsor, you have to use a 4.100" or 4.170" stroke crank to get 427 inches.

With a factory bore Cleveland, you again would have to use a 4.100" or 4.170" stroke crank, but there's less room for the piston. Due to the crankshaft design, you have to use a 6.200" rod, and in the Cleveland's case, that would make for a 1" compression height piston. Normally, that's not an issue, 400 SBC's use them all the time, but the intake valve location in a Cleveland pretty much hampers that idea.

You could also use a 6" rod, but you have to cut the counterweights on the crankshaft down by almost a 1/4", and that gets super costly....then you have to balance it....and that's super costly again.