Other than the motor mounts is a direct fit. You got to cut and weld those back in right spot.
You have 4.10 gears with a 5 speed. So consider that when installing the 6. You will not be able to use the 5speed from the 4 banger. I would install the cherokee trans either if its auto or 5 speed. Wiring can be as simple as splicing in 2 more injectors or ordering a OEM wiring harness from junked TJ that had 6 stock..
Worth it money and time wise, no. Worth it for a learning experience yes. Worth it to get the cherokee auto, yes. Time wise you will have to be on a schedule to do it all in a weekend. Drive shafts will need to be cut and adjusted for the new length.
READ there are a million post on this. Been done to point nothing you will run across has not been worked out and overcome.