Wow sorry I guess I should have thought about this before I posted. I am new to this so please forgive the lack of information ok what I have is a 2001 F350 diesel 4X4 long bed with a 4inch rough country lift and as for shocks it was a kit so I would assume they are the same. I had the lift installed thinking I would run 33's maybe 35's and life would be good but I found a great deal on rims and tires but they are M/T baja ATZ 35.7 and super wide (LT375/65R16). So needless to say they rubbed the bumper and the rear of the fender I was hoping a little boost from a leveling kit would help clear those areas.
Well, your in luck, this application is a good platform to work off of. I work with several different brands, but for this one, I would recomend the 2" RCD Shackle and Hanger Kit. You will probably need to get longer shocks, depending on what is on there now. Some companies use the same shocks on the 4" & 6" lift, so you might be OK. I would recomend a good shock though, Fox or Bilstein Monotubes work real good on these.
As Jeff mentioned, you will probably also need an adjustable track bar in order to fine tune your alignment. Fabtech and Icon make these.
PM me if you need a good local shop in your area or a source for these parts.
This is only an assumption... but your choice of lifts suggests you were trying to lift this truck on a budget. If that's the case the cheapest route to get a little more lift is the Icon 2" front leveling kit (or similar). It's basically a 2" block lift but it installs into the factory spring pack using a longer centering pin. They call it a Zero Rate Add-A-Leaf, and technically it could be considered an add-a-leaf, but it works quite simply as a block. If you've got a set of Rough Country shocks on there now you can run em' til' they blow. If the truck rarely gets used off-road it won't be much of an issue. If you routinely take the truck out in the dirt the correct shock (most likely longer) will be required. The Rough Country cheapo shocks are a generic white can shock that leave lots to be desired in terms of construction and performance. If they blow simply upgrade to a better shock that is the correct length / valving for your truck.
You can space out your factory bumper to gain clearance. It won't realign with the body 100% (that should be obvious) but you can gain a little clearance doing this. If the rear portion of the fender is rubbing you've got 3 choices... smaller tire, more lift, or trimming.
The Rough Country 4" kit uses a track bar drop bracket. Additional lift will cause the front end to shift because the track bar is going to be a little short. FTS451 is the Fabtech part number and it's the nicest cheap adjustable track bar I've seen.
You are right it was a budget first time lift and I used a Pro Comp kit not rough country but I am sure they are close in quality. I was just looking for a little weekend fun without breaking the bank nevertheless adjustable track bar and a 2 inch should take care of the problem.