88 to 91 engine swap?

I came across a rotted out 88 XJ that had a low mileage great running 4.0 in it and I want to stick it in my 91 ho XJ. I will obviously be changing the head and intake and I am pretty sure that the blocks are the same but I wanted to ask someone that knows for sure to be sure.

Thanks!

your 88 has a lot of sensors that the 91 doesnt. as long as you use all the sensors you currently have on the new block youll be fine. other than that it should be a direct swap. i think your temp sender is on the block. on the 91 it will be on the head. as you do the swap you will know what to keep.

The blocks have minor differences. None that will impair a block swap (thats what it sounds like your going to do). Youll want to keep the head from the HO anyway.

Thanks guys that's what I thought I just had to be sure.

Thanks again!