Identifying Between These 2 Starter Motors for an Aircooled CU

[argeetee]

Hi, I’m hoping someone can help me.  I’ve been supplied these 2 starters for my 1982 CU (engine no. CU132770 ). There are a few visual differences to them and I’ve not been underneath my van yet to compare.  

From the photos is it possible to tell which one (or both) is suitable for my engine?

I would like to carry a spare, but am not sure which.

Also you’ll notice the one with the longer cog/gear is damaged  at the rear  end cap of the solenoid where the connection terminals  are. If I have to are the end caps swappable between the 2 units?

Any help is much appreciated. If there’s any more info on the units I look for please tell. The numbers on the main body are only partially readable. Thanks in advance, Ray






Busted end cap...

[Aidan]

I think the correct one is one with 9 teeth, should be VW part number 091 911 023 or suffix X or 091 911 023 A or BX

if I'm right it's the one on the right, be aware the early watercooled version is very similar, I think the position of the solenoid is the difference, but I think the watercooled one will actually fit the later CUs