D44 front axle shaft....not a D50. The 297 caps are the same diameter as a 1350 cap. The 1350 body is wider therefore the CAPS would stick out of the D44 axle yoke by ~ .125 per side and this is where they would weld the cap INTO the yoke of the axle shaft.
Summary: The 1350 caps are welded into the D44 shaft so they are ONE unit.....clear?
I had a front D-line like this for a while but it bugged me as I worried about breaking "some part" of it and being ROYALY F'd. So.....my solution was to lop off the ears of the yoke,turn down the OD of the shaft (@ the ears) just enough to make it smooth for a couple inchs down the shaft.
Then I took this yoke
http://www.ringpinion.com/ProductDetails.aspx?ProdID=2074 and bored the splines out of the ID. Then machined it to an .003 INTERFERENCE fit to the shaft OD. I heated up the yoke(expanded) and dropped it onto the shaft,making sure it was timed to the other ends splines and welded it into place.
Now I have U-bolts @ both the pinion side and the shaft yoke for speedy field repairs