I should probably stick to changing light bulbs. I had mild surface rust in Challenger trunk pan. On the advice of a friend who is an excellent restorer of classic VW's, I bought POR-15 kit and applied the marine clean, metal ready and POR-15. I wanted to at least approximate the exterior color, so I bought my finish coat and primer at a local retailer. They actually scanned the car electronically to match the color. I brushed on the primer, 2 coats. I sprayed the finish paint, also 2 coats, using the little disposal aerosol sprayers. It seemed to work well and I don't think I laid it on too thick. Temp was in the low 80's and I parked it outside for 2 days after painting, garaging it at night. Trunk was open and it got plenty of sun on warm days.
On day 3, I made the mistake of putting the trunk mat in and going to a car show, so that my 1970 could lose a "classic car" show to a 2011 Challenger (another story). When I got home the mat was stuck. I managed to remove it, but it left rust stains on the new finish. I wiped those off the next day with paint thinner on a rag. Now, two weeks later, the trunk pan is still sticky to the touch. Where did I screw up and what do I do? Some areas wiped down to the POR-15 when I scrubbed off the rust stains.