The 3" suspension lift is springs and i did not have to regear. The difference in tire size is on 21 revs per mile. When she goes off roading we will see how hard it is to clean them, i am sure not any worse then mine.
Those are 30.5-30.6 inches tall, so yes basically a 31 and trust me , a regear is needed if you like your transmission etc
It will shift a lot more now, run a bit hotter ( due to extra shifting etc ) plus a little extra weight of the wheels and tires and with the Libertys narrow range where they run best, its a regear game
After 40 plus years of building 4x4s there are not many that can get by when going larger tire sizes without a regear, also 16 years with these Libertys
Good example, I have two Libertys that are lifted one with 32s and one with 31s, both with 4.10s
One road from my place to state capitol is rolling hills on interstate, running the 03 with 31s and stock 3.73s it would shift at least once or twice on every hill when running 75. With 4.10s it only shifts a very few times in the 120 mile trip, does not bog down, doesn't down shift just hit the hill and goes. Better mileage, better on the transmission, runs cooler on the scan guage.
Now you say IT'S ONLY 21 revs per mile but end of the day it is worth regearing