Ok, So here is the deal, the long shaft does replace the two piece shaft. It was in an old service bulletin, not sure what year, the problem is that no one mentions in in their parts catalog. At any rate that problem is solved. The trouble I had with the driver's side was that when I installed the new one, the lobes on the inboard cv joint hit the ear on the transmission mount. I measured both the old unit and the new one and found that the new one is a larger diameter. That too is a change in part design when they went to the long shaft. So, I reached in with my grinder and took approx. 1/4 inch off of the ear and made the required clearance. My old girl is back on the road and the ride is smooth as silk again.
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