That's my experience also. But, there's not an abundance of 95 to 96 XJs out there. We need another solution.
With the ZJ booster, was it necessary to bend the pinch-weld up?
I would begin by inspecting the engine and trans mounts and adjusting the linkage per the video.
And once you've got the transfer case shifting, eliminate the cAD before IT disappoints you somewhere in the middle of nowhere.
The vacuum switch on the transfer case gives vacuum to the CAD to engage/disengage it. That's all. Are you stuck in 4wd or is the CAD just staying engaged?