Very Nice !!!
But the MGs and Mk.19 should have light wash of black, they are much too "bright". They are a dark blue-gray gun metal.
For the Tracks – scroll down look as these pics. TMP link
Rusty tracks with black rubber track pads …
And yes, in the '80s in the US Army our M113s had the .50 with the ability to attach the M47 Dragon MAW.
After serving in 3 Mech Bns and commanding a Mech Co. of M113s, I can be a little picky…
We only saw pictures the Mk.19.
And Yes the AH64 started to replace the AH1 in the US ARMY in about the mid '80s.