Cut strips out of the cockpit combing with a utility knife, 1/8 - 1/4 inch wide and 3 to 5 inches long. there are special tips for heat guns that focus the heat and have a hole to feed the material into.
Aluminum foil duct tape (the real stuff) - put that on the inside.
Heat the cracked area until it looks dull (this is just before it looks shinny and liquid), hold the strip next to the tip to preheat that as well until it is shinny.
Start at one end of the crack and lay the strip over the crack and melt it into place, pushing it flat with either the welding tip or a flat object.
If you can reach the inside weld the inside as well.
Practice welding some of the strips first.
some people talk about using tar backed aluminum patches call "bitchathane" I think.
Haven't seen them though.
friend of the fork, knife, and spoon