Aluminum wheels will rust weld themselves on to, IIRC, high iron content metals. Had it happen this year on my Girlfriend's '00 Mustang GT. Rub a light coat of grease on with your finger before installing them, but for now... WD-40 down the lug holes and a hammer dude.
Merkurs have the same 108mm X 4 lug pattern, unless you have an SVT, they will fit. The front brakes will most likely cause interferance problems on the SVTs with most 14" wheels.
