I inherited my 64 from an uncle. He had driven the heck out of it and used it in a business to recycle telephone poles. I recently got feed up with the sloppy shifting myself. Since my problem was due to the completely worn lever seats (which had already been built up by welding once), I needed to replace the inner levers. I was able to find an entire set of shift components on the web.
I used this old picture as a reassembly guide. Hope it helps
http://morramm.googlepages.com/yb2.jpg/yb2-full.jpgyou mentioned "The connection is not much more than some loose washers and a cotter pin" - mine has the swivel ends running into a large washer with a rubber step washer against the lever with another rubber washer that fits onto the step and another large washer under the swivel nut.