Don't we see the same thing on the seventies vans when they went to EFI?
(circa mid '75 or so).
It does seem likely it's for  a mech. fuel pump.

>  I think Europe got wasserboxers with carburetors, at least in the first 
>  years. That might explain a feature on the case for a fuel pump. 
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>  Dave
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>> Mine has it too.  ('84 westy).  It seems to me that that plate is the 
>> size and shape of the fuel pump hole on air-cooled VWs.  Does anyone know 
>> this for sure.  
>> 
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