Well Mark, you've got it all answered now.

No, you don't need to remove the driving dog to replace the hall sender.

Yes, you do need to remove the trigger wheel, and someone posted how to do
this.  All I'd add at this point is that there's *also* a very small pin
between the trigger wheel and the shaft of the distributor.  Keep track of
this pin because it has a tendency to go flying off into space when the
trigger wheel suddenly "lets go" as the result of the prying with
screwdrivers.

I've removed the driving dog from a couple of Vanagon distributors and I
don't remember the pin being tapered (as somebody said) but maybe I've just
gotten lucky a couple of times in a row and happened to hit the right end of
the pin with the nail punch I used to remove it.
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Tom Young                       '81 Vanagon
Lafayette, CA 94549         '82 Westfalia
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