KB OLDS Block Question

I'm in the process of putting together a 10.7" KB Olds......Will the block accept a 4.750" stroke? I've contacted Ken Black @ Keith Black, and he indicated a 4.5" stroke would swing without clearancing issues, but said anything larger would have to be mocked up and checked. Just wondered if someone here has any first hand experience/input as to whether the block will need clearancing........ I'll be using a Callies Magnum crank w/Oliver rods (steel).

Thanks Dave Moon