I did a variation on this technique and have some pictures and write
up at:  http://snurl.com/vanagon  under Instrument Cluster
Overhaul...   It's also in the vanagon wiki.

Edward

>t 12:56 PM 12/19/2008, JordanVw@AOL.COM wrote:
>>nearly all vanagon instument clusters are going to have some of the screw
>>bosses cracked where the speedometer or tach screws into the back of the
>>instrument cluster housing.  after 15-25 years, its inevitable.
>>
>>they can be repaired easily with JB weld or plastic weld epoxy.
>>
>>i remove the speedo or tach,  and remove the screws.
>>
>>then i coat the screw lightly with grease - not too much.. then wipe the
>>excess off.  i also coat the edge/lip of the speedo or tach with grease where
>>it
>>will come in contact with the plastic welder epoxy or JB weld then wipe the
>>excess off.  i
>>do this so it wont stick.
>>
>>then i clean the cracked screw bosses..and use black electrical tape, to
>>build a "form" or "mold" to hold the epoxy.
>>
>>i then mix up the plastic welder epoxy, and spread into damaged areas,
>>building it up  where the plastic once was.
>>
>>then i reinstall the speedo or tach, and lightly run the screws in by finger
>>pressure.
>>
>>once dried, you will be able to remove the screws..
>>
>>chris