I apologise for the lack of communication with you guys, life has been keeping me busy these days that I can't commit to the project as much as I'd like to at this moment. Despite that, I was able to finish both of the ATF unmarked tahoes recently and took a very brief ( crappy ) video of them.
Thank you very much. I can't thank you enough for letting me use the model, it really is a lifesaver.
I haven't spoiled it yet but I might as well now: the plan is to modify MrMatt's Oshkosh model into a 1980 model as seen on Flickr.