If you want feedback/advice on installing old air units up front in AD trucks, call Patrick's in Arizona. Phil and/or Patrick have installed a bunch and can give you the pros/cons. They are a little biased, but I believe that the Old Air products are a solid unit.
I visited Vintage Air last week ironically while travelling on business. They are a great group of folks as well, but I have no experience with installing their units.
I'd google some AD trucks since dashes are the same. You'll see dozens of examples of pics with vents installed. I personally like the look of the Mark IV that Vintage air is reproducing but am unsure of the cooling power for the burb.
