Best thing to do would be to use some universal steering joints, one at the box and one at the top of the shaft. Use a new double D shaft as well. I did a steering conversion in my 57 Chev pickup and used Borgeson joints (borgeson.com)and a new shaft. shaft can be up to a 30 degree angle with no problems.
I used polished stainless but they sell steel as well...EXCELLENT construction and are all needle bearings, splined, smooth or double D.
89 YJ built tough, NOT pretty
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