<<Connect the free end of the hose to your shop vac and turn it on>>
Be careful.
My shop vac (actual ShopVac brand) used during construction would build
up so much static charge on the structure that I could shock myself
repeatedly after vacuuming.  It was quite fascinating as a physics
experiment, but I would not use a shop vac anywhere near a vapor
source.
  
I don't know how well the IV wing drains, but on my 360 wing I let the
little bit of fuel that was left after draining simply evaporate by
leaving everything opened up.  I don't recall how long that took, but I
was able to get the interior bone dry before proceeding with painting.

Chris Zavatson
N91CZ
360std
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