One thing about WD40 in comparison to other chemicals is that WD40 will NOT hurt your finish at all. As another member stated you can spray it on and leave it for a few minutes, 15 or whatever. I've used the soak and leave it alone method with great results, sometimes it is even better to spray a clean rag and hold it on the area, so that way it will not run down and you get the area good and soaked. Makes an excellent engine de-greaser as well. WD40 can be purchased in 1 gallon metal cans, no garage is complete without a gallon on hand at all times. I also use WD40 to remove caulk from my hands when doing home repairs, in that situation it does 10 times the job denatured alcohol will without drying your hands out so dang bad! Be careful with denatured alcohol, that stuff is really powerful and can do a lot of damage.
Great tips I will give it a try.