Hey 26, I'm pretty much doing the same thing within the next few weeks (SYE and DC drive shaft). I have an '88 YJ and recently put in an AX15/231 TC out of a '97 XJ. I've had them for about a year and just got around to putting them in. I've done a lot of reading/searching reference the SYE/DC. It seems to be what you need to do...if you put a SYE, then you need/should put the DC. You'll also have to get your pinion correct. There's a few posts on this forum that pretty much walk you through it. It's best to do it right the first time, instead of trying something that will likely not work very well. I finally put in my 4" lift last week and I'm doing other things as I'm waiting for parts to show up at my door (UPS). The DC I'm going to be using is actually a front drive shaft from the same XJ I got my tranny/TC out of. I'll be taking it to a driveline shop to have them shorten it and balance it. I won't be able to do that until I take my TC drop out and set the pinion, so I can get the correct measurements for the DC drive shaft. Do more searching on this so you don't run into problems. I hope this helps....good luck....
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