If you're looking at spacer leveling kits they're all pretty much the same. Just pick one.
You mentioned possibly looking into more of a lift- With a 2wd you have lots of options-
CST spindles- 3.5" and your truck will still ride like stock. If you want more you can add a 2 or 3" leveling kit. If you still want more you can use OME coilovers instead of spacers. You should be able to get 4" out of the OME coilovers for 7.5" up front if you want that much. If you go above 3" with the coilovers you probably need upper control arms too.
Once you decide on the front you can start figuring out the rear- CB 3" shackles will get you the first 1 3/4" in the rear. Then you can look at leaf packs or blocks.
For me since I don't plan to go bigger then 35" tires. I'll probably do the Zone 5 kit.
A 3" lift can just fit 35" tires but I would not do a 3" lift.
I'll probably do a 2" leveling spacer for the front until the tires need to be replaced, the get the Zone 5 kit and use the 2" spacers to give me 7" of lift. (But this is subject to change)
Since you are 4x2 I would look into the maxtrac 6"lift then upgrade the shocks with king, fox or icon. You will be around the same price as the big boy companies with the upgraded shocks. The ride quality will be great! That's the route I'd go if I was currently gonna lift my truck. Used to be and regret taking my lift off!
If I were 4x2 I would go the spindle route rather than drop bracket kit. Don't get me wrong the Zone lift is a great lift and I recommend it to anyone with 4x4. The big difference is having the drop bracket that uses up 6" of your front ground clearance. For a 4x2 it's extra hardware you really don't need unless you're going really big- like bulletproof big but that's an entirely different class.
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