You don't want to set your heat gun to 200 degrees for post heating or you will be there all day trying to get the vehicle and vinyl up to temp. As long as the vinyl is in contact with the vehicle it can take a tremendous amount of heat. If you have bubbles or loose edges, that's where you will have problems. Under bubbles the air heats up, expands, blows the vinyl up like a balloon.
If you're have trouble with bubbles in the channels try running you heat gun ahead 2 or 3 times your post heating speed and they will expand and expose themselves. Now you can pop them and go back to where you left off post heating. Also, it is faster to work vertical seams or door edges from bottom to top because heat rises in the metal preheating the area ahead (this is also a good rule of thumb for removals).
I use a Steinel heat gun set to 1150 deg F with the IR thermometer to get a feel for the speed of travel. Then use the IR to spot check the surface temps from time to time. The IR thermometer is important because the speed for post heating is different on every install. The air temperature, sun or shade, temperature of the vehicle, type of material (plastic, fiberglass, aluminum, steel), and the temperature of the heat gun all play a part in determining how long it takes to reach 200 - 220 degees.
There are some areas that you do need to be careful with your heat gun. You can melt the black plastic moldings. You can avoid this by positioning your heat gun father away from the plastic and focus on heating the metal with it blowing away from plastic. The heat will spread out toward the plastic. Another area is where the plastic bumper meets the metal body panel. Vinyl on plastic can't take as much heat so focus more on the metal body panel and the plastic will get plenty of heat. If not you can heat it separately checking with your IR thermometer.
Hope this helps.
