is that .75" per side and is the front as well?
I have an export Rubicon here in Australia, we unfortunately get the lower fenders, so looking to upgrade and need a wider fender due to our tire coverage laws.
don't worry too much with upgrading the sound bar speakers, they are in a horrible position for driver and passenger, concentrate on the front stage around the dash area.
I would suggest upgrading the 3.5" speakers up on the dash to JL Audio C2-350x, Metra manufacture a pod that allows you to...