I am considering putting 6mm wheel spacer on my 2008 F150 4x4 due to the fact that my 305 55 20 BFG KO's are rubbing the sway bar and prematurely wearing out the end links, I have been through 3 sets in the last year. Luckily they are MOOG's and they keep replacing them for free. Will the 6mm make much of clearance difference is my question? I really like the look of 305's and there are not enough 295 55 20's out there to choose from.