Leveling Kit

I've done some reaserch and found that useing torsion bar keys could put to much added stress on your torsion bars and break them, yes i'd still like to raise the front up to match the back.  Any ideas on how i could do this?
 
Also wondering... What size tires could i get away with with minimal rub and a leveling kit?

My dealer did mine for just under $200 on my '07.  I love the way it looks and rides.  I didn't drive it before hand so I can't really make the comparison there.  I know someone that runs 285's under his with the leveling kit with no problems.  There are a lot of kits out there, just google it for your truck and you will probably get more than you need.  Any service/body shop should be able to do it for you also. 
 
Hope this helps.

All i read is you have to use the keys from a ford f-150 and it will help raise it and not have to crank as much. But you can also run 285's on a stock 4x4 truck.