Get the Graydons. The AC's are supposed to connect to the front enging mounts. Two of my friends couldn't get them to fit (the right side was 1.5 inches short of the engine mount)

The Graydons mount to a spline that bolts to the frame and then to the pegs. do the spline first then visegrip them to the pegs to drill the holes. Easy. And if your quad is not perfectly symmetrical, you won't have a problem.