I realize a slide with a fpb will not work on a frame with no fpb lifter. But if the frame has a fpb lifter Will it interfere at all if the slide doesn’t have a fpb?
There is nothing to gain from swapping a Shadow slide on to an SP-01 frame with the Firing Pin Block lifter installed in the frame. The absence of an FPB Lifter allows for a reduction of the Single Action reset distance and SA pre travel. The FPB Lifters presence in the frame makes it so that it requires more Trigger travel to function, with it installed you do not gain the benefit of a Shadow/Non FPB CZ.
If you try to install a Shadow slide onto a standard SP-01 frame with the FPB Lifter installed, the slide crashes into the Lifter Arm. The Shadow slides do not have the relief cut for the Lifter Arm.
So in the end it is a double whammy, there is no reason to do it and it would not work.