the 2nd might have had the motor removed sometime - there were also setups back in the day with a connecting bar externally so one wiper arm made the 2nd move in tandem .... I had 2 motors on a 46 GMC with a 228 that worked reasonably, but vacuum wipers aren't the greatest under any circumstances and when running 2 it doesn't take much push on the gas to stop them dead
Bill
