The model number (first four numbers of the serial number) tells the tale) For instance, for the year 1965
3502 is a Lightwin short shaft
3503 is a Lightwin long shaft
3512 is a Ducktwin (short shaft only)
3532 is a Yachtwin short shaft
3533 is a Yachtwin long shaft.
Only Lightwins and Ducktwins had the weedless drive
Yachtwins all had right angle drive.
So what are your numbers?
