D30 knuckles and discs

I need to know if the discs on my 97 TJ are compatible with the D30 on my 84 XJ. The TJ is ABS.
I'm out of town right now so I can't just try it out.

I also need to know if a knuckle off my TJ will swap with the knuckle on my 98 ZJ. I have a reamed out caliper bolt on my ZJ and I need to swap in a new knuckle. Since I'm replacing my axle in the TJ I though I could use that one.

From my personal expriences I can say there are two disticnt setups used on all jeeps. Excluding WJ as it's all metric.

Setup one is use on older stuff and the outer knuckle is a two piece design. i.e. the caliper bolts to a bracket that is in turn bolted to the steering knuckle. This will be the setup on your old XJ. This setup uses "shallow" hubs and requires the appropriate rotors for use with these hubs and calipers. Hubs bolt pattern is 5x4.5"

Setup two is on all ZJ's and TJ's as well as newer XJ's and some YJ's. This setup has a solid one piece outer steering knuckle and uses a "deep" hub. It requires a different rotor than the setup listed above. This will be the setup on you TJ. Hub bolt pattern is 5x4.5"

So, none of your TJ stuff will swap onto your XJ.
Also, the TJ steering knuckle will be the same as you ZJ so you can swap them. They use the same ball joints, rotors, calipers, hubs etc.