is there a way to tell if the main girdle is the correct one for a block without having to assemble with bearings and spining the crank?

 

I think it´s not possible.

 

ive tried to figure that that out myself when i had a couple of blocks in my garage and you cant just really tell. the best thing to do if unsure is just to have the machine shop fit it that way if its not the right one theyll fix it.