Just called Dura-Lite and spoke with an engineer. (Looked at your sig and saw what you had for a truck... )
He found his notations on the first gen Dodges, '91-'93 and they do make one to fit.
Part Number at a FTL dealer would be DHT DO70A.
They are a direct ship item which means that a dealer has to buy 12 of any number to get free inbound freight.
Call Stoops and see how they would use you, they probably do buy them 12 at a time, to give you some reference I would charge about $900. 00 for it.
I can't stress how well built these things are. As soon as my customers are off the Freightliner warranty coverage I sell these coolers as replacements rather than the OEM coolers.
Mike.