Thanks Stan -- It would seem that your pictures correlate nicely with mine to give the whole idea, then.
Tim/Jerry -- one of the 6400 AD trucks we ... dissected ... at Homecoming a few years back had the HD radiator you speak of (I think TrknGMC ended up with it), but the radiator support was the same as what Stan is showing in his image. In fact, that truck's front clip (with that rad support) is the yard art still at HQ that's about to go to scrap ... I will flip it over tomorrow and double check if you all want me to.