well all your weight is going to be on those front bolts not so much the back, or at least thats what i think. the hitch is soft enough you could always just drill a hole for the 5th bolt hole, bolt the nut strip to the hitch, draw out the hole, mark center with a punch and drill a hole a lil bigger than the dia of the bolt just so you have a little bit of play to work with... thats what i'd do.