Hi all I have been given Super 4 21 base for as parts for a super 4 21 and are wondering what actual parts other than the wheels are interchangeable as I would like to bolt the self propelled system from the 21 base to the 53 base but looking closer while the design and the drive shaft and capstan wheels appear the same It looks like the SP drive unit on the 53 mounts onto the base of the side handles while the 21 the SP drive unit mounts directly to the base. Can they be interchanged without the machining of parts to get the older drive unit to work with the later 53 base.

Thanks heaps

-greg

I can provide pic's if required.