You do not need a heat gun, a ray of sun will work for you in the NW.
if they are painted on you will know by the edges. If they are not abrupt and very smooth as you move your hand down the panel it is paint. If you can feel the edge then they are tape. Just pick at it, you will know in 5 seconds.
Start slow by picking an edge and then just carefully pulling it off, it will break and you will either have to pick at it again or use a Safeway club card (small width plastic credit card) and get a new edge going. Timeconsuming but you can get a side done in about 1hr. After removal you will see the wax buildup and sticky residue. Use goo gone generously and let it soak in for 3-5 minutes. With a soft terry towel just rub the excess residue off the car. Wash then wax your side panels.
