this may be of some help. I have a 1956 model 56R where the driver's side wiper failed to 'park'. An old buick mechanic mentioned to me that to get away from the inefficient vacume wipers, an electric wiper motor from a 1955-57 chevy will bolt right in and still use the transmission cable to activate the switch. Much more efficient. This had an unanticipated side effect: it tightened up the cables so the wipers parked correctly. Turned out that the dimentions for the pully was slightly different for the chevy version making it a bit of a challenge to install.After this was overcome and bolted together,everthing tightened up and has been OK ever since. That was done in 1971. Making this change will get away from your car from being 'original' but this decision is up to you.. Just thought Id throw in my 2cents worth.
