Sean- I thought I would post some interior pics of the Mengshi for you- Hobbyboss didn't have the interior colors anywhere near correct on the original Mengshi kit. That being said the PLA seem to mess around an awful lot with their interiors- there are several variations of interior colors, trim, equipment etc. The most common interior coonfig is the standard grey set-up;

That picture shows the door inserts as green but they are also commonly seen in the same grey as the floor- a slightly darker shade than the dashboard. The picture below shows the seat shades- the pic is from a Police vehicle (I think) but the seat color is fairly common in military variants:

Sometimes the military also use camouflage seat covers:

Also- the armed variant you are doing is present at the PLA Museum in Beijing but I think it is quite an early model (I think it has been there since about 2008) and so the seats are darker but it does show they don't have head rests attached apart from the driver- I believe this is a common configuration for the armored variant:


I hope these help you out a bit Sean- if you need any more pics let me know.
As to the trade deals I was talking about- some basic info is provided
here at SinoDefence.
And, as far as I can tell, the Hummer brand was not bought by a company called Sichuan Tengzhong- the deal, according to various news websites, never went through. I thought this was the case but Gino made me a bit un-certain as it could very well have gone through and we could never have heard anything from Hummer again, beyond the Chinese market- as happend with British MG Rover- the MG brand is making a return but Rover (now Roewe in China) isn't and is a China only make.
A Hummer enthusaists website,
www.hummerguy.net also has stuff about the fate of the old company (nothing to tell really- it got shut down and just has a website for parts- still offically owned by GM but there are no staff or dealers etc). Interestingly, it seems AM General are going to release a new civilian Hummer!
The SinoDefence article does mention another company, Shenyang Aircraft Corp., and as far as I know they did build a version of the Hummer but I don't think it was taken on by the PLA.
(Apologies for being so long-winded, I'll shut up now

! )