I would be afraid of the copper leaving a stain on the paint
underneath and on that small strip between the window/luggage rack. I have never used copper screen
so not sure of how much copper is really in it. 
I have used stainless mesh just glued to the underside after
forming a small "bubble" shape pushed up through the drain
hole. I found its less likely to get blocked with debri this way
and still be able to drain. 
This reminds me of a few years back after just buying a
Westy for a quick flip. My wife was joking around by standing 
in the road blocking my way. I drove up fast and stopped quick right in front of her. A large slurry of rotten leaves and
slimy water came out of that rack covering her with the
nasty mixture. To say she was very unhappy is an understatement. My son and I found it funny though. 

Bill
87 Westy
Zetec Turbo

On Aug 7, 2012, at 11:11 PM, Stuart MacMillan <stuartmacm@GMAIL.COM> wrote:

> I like the idea of the stainless steel mesh glued under the drain holes.  We
> have tons of tree debris here in the northwest, and it will keep the wasps
> out too!   Copper screen will work too.
> 
>