Thing to remember on 1 ton trucks, they sit higher than a 1/2. I did an SAS on an 89, ORU brackets, junkyard 4” springs, towered over 35s. Granted they were older n tread getting low, but compared to a swamper they run small. I put 36s on it and looked perfect. Brackets will give you 3”, so add that to whatever spring you use. 8-10” is still pretty big, the 89 got 8” springs for total of 11” or so n I ran 40” boggers. Im doing an SAS to 96 Yukon, going for 5-7” of overall lift. I’m not going over 35s, but I’m using 52s, n here they can give more than 4” of lift. But I’d rather have a touch more lift than too big a tire. IFS flexes different than a solid axle so need to account how the tire moves in the wheel opening. You usually can get a dually axle cheaper than a single, since most people want the single. I’ve seen a bunch on marketplace lately. Even found a front Dana 70, something been looking for since I knew what a front 60/70 was.....