‘71 340 Duster Front Drum to Disk with Factory 14” Rallye Wheels - Problems
good news! you can swap out your rotors for 5X4.5" in that all of the rest of the components are the same. this gains a whole host of options in rims.
it still sucks that the repop rims won't clear the calipers, and you could always maybe grind a little off the caliper body and/or space the rim out a touch to maybe make it work.
so you at least have options