How to use a vertical shaft lawnmower (with auto drive) in a go kart?

I have an old hayter Harrier 41 Autodrive VS ( http://www.hayter.co.uk/products/homeowner/mowers/rear-roller/harrier-41-autodrive-VS/ ) and me and some friends wanted to use it in a go kart. I was wondering If I can modify the auto drive to run at the same speed as the engine or will this cause it to fall apart. If I can't do this will I have to use a bevel gearbox.