Technically, the G is not a real designator...it refers to a T-72 built outside of Russia that really became the T-72M. Just so you don't go looking for T-72G resources and cannot find anything usefull...
The DML kit, as all fo them, is long in the tooth. The G/M turret in this kit is the most accurate of all of DML's T-72's, but like all DML kits, it has the problem of being innaccurate due to the age of the kit.
Any detail sets for the Tamiya kits WILL NOT really work on the DML kits without some serious work and adjustments...you would be better to scratchuild any detail changes.
You really have three choices to make:
1. Work with what you have and scratchbuild any details you need. Try to aquire the Eduard PE set for one of the DML kits (they are now OOP).
2. Get the Tamiya T-72 and gently put the DML kit out to pasture.
3. Another option would be to get the SP Designs TOS-1 conversion specifically made for the DML T-72 kits. This would raise the detail level, look inspiring, and get you some good experience doing resin conversions. And, of course, it is a shameless plug for me to help SP Designs out.