You could make a slot antenna? ie cut a rectangle out of the metal sheet
(say) 2" wide and a little over 1/2 wave at the op freq. From memory
you'll get pretty close to 50/75r and the polaraisation is 90deg to the
slot.

Doubt it helps but worth a mention..

Cheers Bob VK2YQA

Dan Jacobson wrote:
Assume there is only one spot on your hilly land that you can pull in
your favorite FM station, 90 Mhz, over the competition, and only with
a horizontal dipole at a certain azimuth. A Yagi doesn't help, as
we are depending fully on the null.

Assuming we are stuck with this position, how can we enhance our
dipole? I am the owner of great sheets of metal. Can I put my great
sheets of metal to use in e.g. a dipole made of two great sheets of
metal?