Well, I did a bit more testing today with my son, and to my delight we actually found an easy way to start the kart with simply using a tow strap and pulling the kart with my truck. It's a little tricky especially when the tires are cold. Here's how I finally figured out how to do it. The only gear that allows the engine to bump over is 5th. I also need to use LW's compression release, and we need to get to a speed of about 15-20 mph, and I need to keep using the clutch as the rear tires tend to skip bounce and loose traction. Cold starting is the hardest, once the engine is hot it's way easier.
I also fixed the engine stop by adding a second stop bolt, loctited the engine mount bolts and I also cured the fuel leaking out the overflow hose by dropping the float height. So at this time the kart runs excellent. So now it's time to practice get used to the horrific power and shoot a good vid !