I have a B&M 24,000 GVW cooler (part number BMM-70264 $49.95 from Summit Racing) on my truck. This cooler is black in color and includes all the hardware necessary to install it (including rubber transmission hose). The larger "race" cooler you saw was probably B&M's 28,000 GVW cooler (part number BMM-70266 $59.95 from Summit Racing). This cooler does not have any hardware due to the custom nature of this coolers application. The fittings are 1/2" NPT too BTW.
In addition to the B&M cooler, I have a remote transmission filter also. Part number SUM-G4980 from you guessed, it Summit Racing. The filter is installed in the pressure line up stream from the radiator cooler followed by the B&M cooler before the ATF goes back to the transmission. I have a temperature sender in the remote filter housing (it comes drilled and tapped for 1/8" NPT senders) to monitor the temps in the transmission.
http://huryde.station180.com/gallery/view_photo.php?set_albumName=mikecampbellakaSY2932&id=abe
A deeper cast aluminum TCI transmission pan (part number TCI-378000 $121.95 from Summit Racing-hey, I live close by

) completes my cooling setup. Even on hot days in the summer, my tranmission never gets over 170ish degrees. My gauge is programmed to alert me if it exceeds 200 with a warning light. HTH's
Mike Campbell