When I was putting my 59 together a few years ago, I bought a new clutch fork from McLeod. I have a small spline Toploader in my 59, so I bought the small input clutch fork, but McLeod showed 3 different forks available, including the big input Mustang unit. Price was very reasonable as well. The fork I got was the later "leaf spring" style, so I bought a new fork pivot fulcrum, with the slot for the spring from McLeod at the same time. I much prefer the later style spring and pivot, over the early wire clip version.