MJ the pic of your GrandPa sitting on the running board looks like it could be of a '36 chevy low cab or '37 GMC tough to tell since the trim lines above and below the door handle are the same on both models. Great photo to have
I may be wrong here as what I see from Googling 36,37,38 Chevy/GMC Trucks both 36 & 37 look alike as for the two trim lines below and above the door handle and what I have seen for the 38's the lower trim line looks a bit wider/thicker from the top trim line. Its just what I see, I maybe wrong though. Others with better knowledge please set me straight.
Thanks in advance.