Topdog
Be aware of the spring pad width changes after 1975 You may want to bee prepared to cut and remount the perches from anything post 76. I am not sure if 72-75 is the same width as yours. I believe the pumpkin is on the same side on all D30 from Jeeps. Good news is if you find the 72-75 D30 just grab the discs from a disc equipped 30. Take them off with the knuckles as an assembly. I don't think the early knuckles have mounts for the calipers.
Remember 72-75 D30's came with 11 inch brake drums, better than your 27 setup if you don't want the extra expense
Happy shopping
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75 CJ5, Flintstone floorboards,dents, lumberwagon suspension, 31 muds, Warn 8000. In otherwords...Stock