Thanks Andy, I had found that before and leafed through it, but you're reminding me I need to go through it in more detail, lots of interesting stuff in there.
@Fallout2077: Correct on the T-80B in the 27GMRD. However as far as I can tell only the 31st Independent Tank Battalion received the T-80Bs in 1982 (they exchanged x51 T-62s for x40 T-80B, organized into companies of x13 each). I am not sure when the 68th GMRR, 244th GMRR, or the 28th TR received the T-80s; I know that the 243rd GMRR got theirs between 84 and 86 (found this info on GSVG veteran forums). In the absence of positive data, I'm assuming that by late 1983, the 31st ITB is the only formation in the 27th GMRD to have the T-80B, given the painfully slow and fragmented nature of the T-80 introduction.
Regarding T-62 models, I'm not sure. As far as I can tell, the Soviet records make no distinction between the various models and upgrades, a T-62 is a T-62 is a T-62. I do know that vehicles generally only received upgrades when they went in to depots for periodic maintenance/overhauling, but the time between these depot visits is measured in years, as most vehicles (apart from a "training set") were mothballed most of the time to prevent wear and tear.
I am pretty much certain they would not be T-62D or T-62M however. The Drozd system was championed by the Naval Infantry, and they were the only users of it (they eventually abandoned it). The T-62Ms were mostly an Afghanistan thing if I recall correctly. More modern tanks were not sent there, so measures were taken to improve the survivability of the T-62s there.
Also, the T-62s in Germany were scheduled for replacement soon, so why bother going through the expense and hassle of upgrading them when tank crews were dying in Afghanistan?
So I would say T-62s in 8GA could be Obr. 1967, Obr. 1972 (with DShK AAMG), or Obr. 1975 (with KTD-1/2), any or all wouldn't be wrong in my opinion. I would aim for a mix of types, rather than all one type, as again it was mostly based on when the individual tank went in for services.
Hope that helps!