>The approach I would use would be to remove that black plastic floor
>duct entirely and then use the heater cover you have. The black plastic
>floor space hog is only held in place by a few screws hidden by caps.
>There is nice clean carpet under it so removing it looks fine when you
>are done.

This is exactly what I did.  I liked it better when removed, more space and
more heat up front.
I stupidly threw out the heater cover and black plastic floor duct.

Gary Lee
http://www.telusplanet.net/public/gary2a/vw.htm