Ditto on the electrical tests. A manual generally trumps a video for me. If I can't get one I go to bikebandit.com and look at the parts schematic. I don't have much confidence in spray cleaners. Use a cleaner where you submerge the dis assembled body and use something like a welding tip cleaner to clear the passages. You hear a lot about damaging jets with such things as wire taken from a brush or frayed control cable, but I have never seen it. SeaFoam is a good product. Keep it in something airtight and reuse it
Since you are casting doubt on your spark, concentrate on that. Grounds, caps etc. think sandpaper. Clipping the cable end, and a new under 5 dollar cap. Auto parts stores probably have similar ones to what you have on there.