Discussed matters with my buddy who has been a machinist for 30 years and builds Bugs and stuff in his spare time. He's never had a VW beam "this far apart." He offered to turn me up a carrier out of aluminum. I told him what Carey said, above, and we thought about what the other three corners of the beam held in store. All agree the best option is to R&R all the bushings and bearings in the beam with white Delrin. Ordered same.
I'll see if Cip1 will take back the unused bronze bushings and the one bearing I bought.