Wow, accumulator that is pretty nasty stuff she ran into!
It is indeed the LLUMAR on your DENALI.
Chefwong, the stuff that you are talking about was actually (someone can correct me if I am wrong here, but this is my experience which is backed up by my rep) much more clear than what is out now, or what is on accumulators truck.
FWIW, LLUMAR had problems with the film being *too* clear--made installs difficult, roller tracks(frost) in the film, etc. They added a little op into the film--this was the version that I used on accumulator's truck. A few months after that, more texture was added and the "frost" continued. My rep finally told me that for *my* customers I should use ventureshield film.
I tested it out(takes a while for us because before I will switch I long-term test it for durability) and it is very nice film. It's certainly not as clear as the first two versions of the LLUMAR, but it installs beautifully, is very durable, and looks great when installed properly. It does have a bit of "grain" as opposed to op--if that makes sense.
FWIW, my LLUMAR rep told me that the "tolerance" for their film was 7ft. In other words, as long as it looks good from 7ft, all is well.
I told him that for my customers (as well as myself), it was more like 7 inches!