Technical Model A Engine choice/sizes

Ok Friends.
Need some help.
im looking for engines for my Model a build.
Is a 54 322 Nailhead longer than a 53 331 Cadillac?
And yes! I know of the starter location issue on the nailhead.

 

Anybody know?
The Buick has a early Ford trans on a adapter.
I have heard that the buicks are longer than most v8 engines.

i dont want to move the radiator/grille. And want the most leg room possible.

Is it a better choice size wise with the caddy?

 

The Buick is LONG!
Too bad that listing dont have the early caddy 331 messurements.
But thanks!