David,
I read an explanation of what the scoop vents are for on the list a few years
ago.
The vents are for equalizing the air pressure for the air-cooled engines,
which have a tightly sealed engine compartment. Without these vents, a vacuum
would be created, and the engine would overheat. (just like the earlier
busses).

They don't really force air into the engine compartment as it is believed.

It's a great place for the air intake snorkel, so it should be a good place
for the intercooler.
If you want to force air through the intercooler, an inline fan, like a bilge
blower, might work.

Robert Keezer
1982 Westfalia
Seattle