The easiest way to tell is the Cleveland has the water outlet on the block - the Windsor has the water outlet on the intake manifold. Valve covers are different so you could still tell the difference on a 1/24-1/25 model if anyone is picky.

The Nascar is a a race only hybrid - basically a 351W block with 351C heads - but I used to use them all the time in models when the kits were cheap (like $ 5.00 cheap!) :-)