Been working on a XJ D30 for my TJ and want to install lower bump stops. I've found instructions showing drilling holes in spring perch for a thru bolt and nut on the bottom. I've only seen it done on the side you have access to the underside pof the perch. Then goes on to say repeat the procedure for the other side.... Well the other spring perch has no access to the under side. How are you supposed to put a nut on the bolt under the perch? Can I just drill and tap the perch for the bolt and leave it at that? That method does not seem very durable or is it?