Cranking the front tbars wont' do anything for your vibrations. It will only move your A-Arms down more, not dealing anythign with U-Joints in begin with. Thats why when cranking the tbars, you don't need to worry about U-Joint angles, you are dealing with CV Joints.

You have to fix that rear angles so they match up. JorgeA listed two ways to do that. If you dont' understand, I can post generic pictures to show you visually.

99 Montero, 3.5 L, Auto, Front/Rear Lockers, 2" Body Lift, 35's, 4.90's, Rock Sliders, Front/Rear Recievers