The caption says "new configurations". I wonder if that includes doing away with a separate M16 MGMC selection and including that variant under that same M3 chassis, but choosing that option in the hanger??? It would make sense. Similar to the M4A3/75mm and the option of mounting the Calliope rocket launcher on top: same vehicle different load out.
I just looked up the AP performance of the 75 mm gun M1897A4, at 1000 yards it can defeat approximately 32 or 43mm of armor at 0 degrees, depending on which AP ammo HTC chooses (odd though, the older AP round penetrates better). So don't plan on doing much but ambushing and hoping for that side or rear shot, it appears. The HE capability seems to be pretty revered though, as does the rate of fire at 20 rounds a minute ("with an experienced crew", according to my source)!
