Small bolt pattern disc upgrade

That kit is just a 73+ factory disk kit with rotors that were drilled for 5x4” and possibly with a center hub that was turned down. Looks like the same kit that pirate jack was selling.

I’m going to go out on a limb and say the source of the rotors is the same, so you may have issues. Just do a search on the pirate jack kits, people have had issues with the rotors being out of round.