I.D. Small Block Chevy

[ClassicCar.com]

Hey all you chevy gurus - Is there a quick and easy way to tell if a small block chevy engine is indeed a 350 with out digging up the casting number, or any of that type stuff?? I am looking at an old van (for the motor) and the guy says "I'm pretty sure it's a 350." Well I'd kinda like to know with some certainty BEFORE I buy it.
Thanks! /ubbthreads/images/graemlins/grin.gif
Dave. K