Is anyone able to verify, by measuring their truck, what their bumper-to-bumper length on a 2015 or 2016 crew cab, long bed is? I am looking between 3 trucks to purchase my first duramax. 2 of the 3 are long beds, which I would prefer, but parking in the garage is more important due to the winters around here. I have found 20'-8", 21'-6", and 21'-8" online and would rather get it straight from the horses mouth what the overall length is. Thanks in advance, Jed.