EIGHTEIGHT_GT
Founding Member
IUP is described in a couple of the posts above. The Sport Interior Package gives you the nicer steering wheel and shifter, metal interior door handles, metal petals, and vinyl inserts on the doors. Your dash would be black (or parchment, I guess) without the silver panels. You do not get the MyColor, message center or the extra two "gauges".
I thought that premier trim package gives you the aluminum pedals and bezel around the shifter while the IUP gives you the metal door handles? I believe that sport interior package gives you two tone colors, but only available in certain combos with certain options.
I still wouldn't buy the IUP because it doesn't offer any performance, handling, or fuel economy advantages at the extra cost. The trip computer should have been standard on all Mustangs so I refuse to pay extra for the toy. In addition, I absolutely despise chrome surfaces inside and outside of the car. The black alloy weave doesn't really impress me enough to shell out the extra cash for the IUP.