It does not look that difficult to remove the UIM to change the plugs on my 2004 Sable. Replacing the UIM gasket is recommended. Is removing the old gasket difficult in terms of removing the old resude? Do I have to scrape for hours for the mating surfaces to be clean? What is the best way to remove the plastic retaining pins on the accelerator splash shield? I am also investing in a torque wrench to do the job right.