trying to keep her cool

Ok, on hot days running in traffic my car will get hot, new radiator, put a clutch fan and 6 blade fan. Would like to install trans cooler. What's the best cooler to use? And I would like to locate some where out of the way and use stainless flex lines. Checked around(Summit & Jegs) can't seem to fine lines. Any one know what will fit? 67 Dart 360 crate with 727 trans