I have an old Napa catalog but it doesn't show anything for 66 except air brakes. There is nothing wrong with putting kits in as long as the wear area of the cyl. is not pitted. The clutch part is usually OK as it takes a full stroke each time.
Also if you have the time you can send the cyl. out & have it sleeved in stainless steel or brass.
Last edited by Wrenchbender Ret.; 12/23/2013 5:21 PM.