Clutch linkage problems

With the bellows removed from the window in the BH, where is the fork front edge,relative to the front edge of the window. In other words how much room is between those two, in approximate inches? Like 1.5", or .3" etc
With a 10.5 inch BnB, the fork should just barely have room to put the bellows in.
A 10.5" CenterForce diaphragm has a bit more room, not much but Ima thinking no more than 1/2 on mine.