Contact them, They should be able to get you schematics and parts.
Those were fairly basic engines. Run through the whole fuel system first to clean out everything. Make sure the electric is solid also. You should only need a wire from the plug to the coil and from the coil to the exciter. the others are for lighting and shutting it off(grounding) if the shut off wire is pinched somewhere it will never start.
BE VERY CAREFUL on the carb. The aluminum is brittle and prone to corroding the metering screws. I've broken quite a few on sleds and once you break it you might as well just throw it away and buy a new one because they will never work right after.