In a message dated 97-06-14 18:43:20 EDT, CBraymen@sculptured.com
(CBraymen.sculptured.com) writes:

<<    I've got the same question. On my '84 there is a hole in the bottom of 
      the drain pan below the computer, but it is plugged with a small piece 
      of rubber.  Same on the passenger side.  My neighbors '87 doesn't even 
      have the hole.  Where is water that collects there supposed to go?  I 
      may just remove my rubber plugs.
       >>

They've been using those drain "plugs" for years in the rear battery trays of
the buses and vans.  They are spaced up off the hole, so when clean, water
will drain out from above, but road water won't spash up from underneath. 
Try cleaning around them, and the hole, and water will drain out. 

chris