I did something similar by raising the axle all the way up with a block of wood between the skid and the diff cover. Loosen the skid, let it squeeze and shift, and then tighten it back up.You don't have to cut them. See the depth of the slot? Wedge a chuck of 2x4 off of the cargo step and use a prybar on the end of it to move the mounting flange back to the limit of the slots.