Its pretty straight forward to ball park gearing changes to compensate for tires.
Just divide the new tire by the old tire diameter...and you get a percent change.
IE: Your RPM at any given speed will DROP by the percent LARGER your tire is.
So, go to from 30's to 33's, and that's ~ 10 %
If you were at 2,000 RPM, the added diameter will drop you to ~ 1,800 rpm....and so forth.
To go from 30's to 35's, that's a ~ 16% change, so your rpm drops by ~ 16% from 30's to 35's.
So, if you were at 2,000 rpm on 30's, you're down to ~ 1,680 on 35's.
If your stock gears with the 30's was 4.6, for 35's, you want AT LEAST 16% back, so that's ~ 5.3 instead of 4.6. 5.13 might be as close as available, so, you'd get that, etc.
Also, the larger the tire, the more gearing you need JUST to compensate for the added rolling resistance...so, 35's are a handful for an X.
Off road, adding lower t-case gears can get the rpm up to better torque levels near idle, etc....but won't help ON road, etc.