Dont call the 400 a "Cleveland", a "400C" or a "400M", unless you want to get Davis all excited.
The fact is that the 400 looks like Cleveland, but has a taller deck to allow for the 4 inch throw of the crank, just like the 351W has a taller deck when compared to the 302W, to allow for it's 3.5 inch throw.
Every part from a 351/302 Cleveland will go into a 400, except the intake and pushrods. Obviously they also have their own 4 inch crank (with big 351W sized mains) and their own piston/rod combo. Nearly all 400's were tooled to fit the C6.
You may enjoy this thread . . .
351C Stroker vs 400M