Cary, the bolts go thru the mast with washers and self locking nuts inside the mast. Just take the bottom plate off and place it low enough to get a wrench on the top screw. Do the top one first or there is no room to get the wrench in The mast is pretty thich there, or you can fill the very bottom of the track with epoxy and drill thru it and the mast for extra support, Rick