My ’78 came with a 100mm square beam already in there. With the 32” wheels they were very close to the beam so I angled the beam down towards the bottom in front of the wheel. This created More space for the tires.What should I clear out? the new beam is the same dimensions as what I'm cutting out?
I don’t know what size tires you want to run but it is much easier to do before you put it in.