if you sat a stock 2wd MJ next to a stock 4wd MJ, the 2wd will be about an inch shorter. So if you added the same spacers and shackles to both trucks, both trucks would be 2" taller than they were previous, but still the 2wd MJ would be 1 inch shorter than the 4wd. But all of this is moot since a bone stock 4wd can run 31" tires (on stock Jeep rims) so the 2wd will look like a 4wd with a 1" lift and 31" tires.
In order to get the 2wd up another inch, you'll need to buy springs, either used, new or whatever. I wouldn't sweat it too much. :thumbsup: