Is there a difference for 1988 xj latch on the rear lift door? I've tried two replacements, but the little striker plate that triggers opening only moves to the left like it's locked, but when I turn the key, it doesn't move to the right so that the button hits the striker.

 

Can you take a picture of what you're working with? I went and took a look at the latch on my '88 and I'm not sure which part of the mechanism you are asking about.

 

This came from a similar cherokee at a salvage yard...couldn't find a new one on line. What I referred to as the "striker", is the white boxy looking gizmo. When the button is pushed to open the hatch, the box has to slide to the right so the button can hit it. A cam on the lock cylinder slides the box left, but turning the key will not slide it to the right so the button can press on it. Make any sense? Note: the picture is about 25% bigger than actual size.

 

I believe you are describing the action of the mechanism correctly. I apologize but I'm not going to take the interior panel off of mine to get a better look - they don't take kindly to being removed and I'm pretty happy with the last installation with 3D printed Christmas tree holders.
Just to be sure, you are talking left/right as viewed from the front of the vehicle, right? Looking at the lock itself, it is keyed so that it will only install into the tailgate in one orientation. It seems very mechanical. If turning the key does not slide the white box, perhaps the cam is not moving. The lock pictured is from a '90 donor vehicle. It did not have power locks and the latch mechanism was slightly different than my '88 with power locks. Is it possible you have a complication with having a power lock latch without the power lock actuator?

 

I think you may have hit on it. My '88 has power locks...not working right now, wiring is chaos...I thing there is a push/pull rod that attaches to the one inch bar with the empty hole and when operative, pulls the boxy mechanism over, allowing the exterior push button to actuate the latch release. Your description of the power lock must be the difference. Thanks so much...I'll pursue that idea ant post back to you if that's correct. It may be a while...the wiring for the power windows and door locks is a nighmare right now. Again, thanks for your input.

 

Before my hatch power lock actuator was functioning again, I could still lock/unlock the tailgate with the key, if I remember correctly. If the power lock's lever is in the unlocked position you should be able to open the hatch and lock and unlock with the key. Good luck