One option would be a Mancini "Muscle Car" radiator. It is top tank aluminum and made (quickly) to your specs provided on a form. I run a 26" version on an E with 496 and AC and it cools great. I just had to re-order after a full truck tread on the road took the old one out.

Specs in on Monday, shipped today. They can put the water connections wherever you want them. My "old" one was in place for ~10 years with no cooling deterioration. A coat of radiator paint helps it blend in somewhat.

http://chucker54.stores.yahoo.net/manciniracing27.html