I finally did this upgrade last week. The DS1238 works perfectly, it appears to be identical to the OEM TJ part (DS1430). Why they have different part numbers is beyond me. Price-wise Amazon grand total was about $50 more expensive, and RockAuto quoted $16 to ship everything so the choice was clear.
I had similar questions & it's easy to get confused by the overuse of the phrase "tie rod end", but now I have answers. If you weren't confused going into this, I'm happy for you. This is for the rest of us, hopefully it clears up some confusion for those of us mere mortals.
On the drag link (the part that goes to the pitman arm), the pieces are all the same as OEM; no actual changes. There is a long end (DS1238; this is the XJ part), a "short end" (ES3096L, same as OEM), and a coupler (ES2079S, same as OEM). You can likely re-use the coupler, but the short end is probably worth replacing.
On the "tie rod" (the part that goes from the driver knuckle to one of the holes on the drag link), it is all new pieces. The OEM is built with 2 sad little tie rod ends that thread into a long skinny tube, so nothing is reusable. The ZJ upgrade is as follows: a "long end" (DS1312; this is the only ZJ-specific part), a "short end" (ES3096L), and a coupler (ES2079S).