Try and find a Borg Warner or BTR transmission cooler, same setup as the factory one, only bigger. There about the same price or maybe cheaper ( I get quoted $120 at trade price).
Im not too sure about Davies Craig ones, never used them. I've only used the Borg Warner / BTR ones.
"Give me any task to do, and I will find something else to do in it's place." Plato - a definition of procrastination