Actually....
An 89 should clear 31's if you have good springs. At most a 2" lift should do the trick. 33's will take a 3" lift minimum and a 4-5" lift would be ideal. I now have 7" of lift and we'll see how the 35's fit after I get the front axle back together.
Stock on 31's with factory rims.
3" lift and 31's
3" lift and 33's
5" lift and 33's
7" lift and 33's
To get the lift, I used a lot of info off of the tech archives on here. I went with a 2" body lift (which is about perfect, IMHO, for making the drivetrain sooo much easier to work on), I used a pair of 3" James Duff coils and a set of JD axle pivot drops in the front. Did custom front extended radius arms (it's been talked about a LOT in the suspension forum), used F-150 spring perches in the front (3" coils plus the spring perches makes for roughly 5" of lift), 4-door explorer leaf springs with an extra leaf in the back and Belltech chevy drop shackles for 5" in the back. Took my extended and collapsed shock lengths to a local auto parts store and had them match me something up. Had to buy a drop pitman arm. Front brake lines were extended using info from the tech archives. Rear brake line was ok for length but when I replaced it, I used one for an 88 (IIRC) because it's about an inch or so longer. Offhand I'm not sure the wheel size that was used on the 33's, the 31's were on stock rims, both steel rims and alloys. There is a thing in the tech archives about rim size, I went by those guidelines and ordered rims to put my 35's on but have not had a chance to try them on the truck yet because I need to get my front axle back together.
