Grand cherokee rails will not be a direct bolt in.
They can be used only with moderate fabrication. I believe the front mounting points match up but the tabs must be bent, the rears may need something like welded angle iron and drilling to mount in stock location.
Not 100% sure, others will chime in.
Using bits and pieces of info from all the available write-ups, I swapped in ZJ leather/heated/power seats front and rear.
I just unbolted the seats from the rails. However my xj only had power driver seats, the passenger seat is powered, but is bolted to my manual rail. the passenger seat is stuck in a gangster lean until I can swap in the ZJ rail...