and while the crossmember is off, I make up new flanges for the rail ends since they are almost always thin or non existant.

as a side note, look at the tailpanel on this car. No spot welds! this is a virgin car, yet the tailpanel was mig welded on to the trunkfloor. Under all the factory paint and seam sealer. Proof that the factory didn't always do thngs as planned. I suppose the spot welder was broken down or the guy went on coffee break! Not the first time I have seen this on old Mopars.