When I am done with my install the stove pipe is only going to be about 2 inches from my non-combustible heat shield which is going to cover the 5' wide back of the hearth from floor to cieling(with 1" airspace on the top and bottom, sides tight to the wall. My heat shield will be about 3" thick when done (natural stone veneer on durock). The measurement from the stovepipe to the drywall is exactly 6 1/8" and it requires 6". Do I need to take a pic of this measurement for the inspector as there will be no way to prove it once the heat shield is done? Would an inspector even beleive the pic?