P-30 front end parts

I posted in July about how my RH lwr ball joint suddenly failed while rounding a LH curve and the whole front end just dropped causing the tire to blow and the floor to be pushed up. I suspect that that the shop that rebuilt the front end 2 years ago put the wrong part in. I have read on here that pick up ball joints have been mistakenly installed. Does anyone know the right part numbers for the lwr ball joints and lwr control arms for a p-30 chassis. Also do heavier P-30's require a heavier duty ball joint and lwr a arm that the smaller chassis? MH is still in Mt. waiting to be repaired?