exactly, it will increase the radius of the swing, if im thinking right the little bit of lift will prevent that

 

I would not add a block under the front leaf springs. In the long run other than a ton of other reasons, you can weaken the leaf spring and increase the front axle "rap/flex" when stopping. I would look into lift options to gain the stance you need to clear the tire and wheel. You should be able to find something with in reason of $$ that will be better in the long haul.