FM 100-60 really isn't supposed to reflect anything in reality. It's a "capabilities-based" OPFOR model, intended to provide a "World-class"
(Excuse me, but the TRADOC bureaucratic inanities turn my stomach)
selection of the most capable threats throughout the world. That means some things may be former Soviet or Russian; other systems and organizations may be drawn from other sources: Cuba, North Korea, what have you. There is no intent for it to absolutely mirror current ground truth. And it's twelve years old now.
(And it is based on an asinine concept, since when it was developed and published, US troops were surely going to be, and now are, facing adversaries that don't even vaguely resemble any portion of this kluge. End of paid political announcement.)
The Russian ground forces have continued to develop, with some interesting changes. They're not so easy to dig up on the Web. I'll leave it to others to point you to the right sources, as I'm not in that business any longer!
Allen