Ok, here we go…
I’m going to build a T-72-tank and i’ve been looking at one billion pictures to find out what the difference is between them all… 
i want to know how to spot the dirrerences between the versions… And i stick to the most common versions to start with…
Here is some differences that i’ve found that are easy to spot…
Early variants didnt have this extra glacis armour (A on pictures)
Early variant also has 3 splashlines instead of two… (B)
The early tanks had 8 spoke wheels and later had 6…
Whats this (C) ? … i’ve not seen it on many models but still…
Later models had smokegrenades (D) from the start, but earlier could also have these added…
Is this (E) the optical rangefinder on earlier models?
If so, then this (F) should be the laser rangefinder on later models… correct?
What is this (G) that i’ve seen on the top of some t-72’s?
Even sometimes on the inside… If it’s the same thing as above…
And then there is the hardest thing… the turret… Sloped or more vertical… Standard, Dolly Parton, or Super Dolly Parton… I just fint it hard to spot the dirrerence and can’t even provide good photos with the differences…
Please if you know… then comment if what i write is wrong or right and fill in the blanks…
Cheers!
Here is a fairly decent T-72 thread with links to other T-72 threads. It’s a tank that’s been in production for several decades in multiple nations so there is a wide variety of variations.
http://www.network54.com/Forum/47209/thread/1300646016/Tamiya+T-72+turret-+Good+-
Yes C and E are the optical stereoscopic rangefinder from early varaints of the T-72. F is the later laser rangefinder. G is anti radiation protection that was added in the 80s when the Neutron Bomb was a viable threat to Soviet armor.
You are on the right track, but as Rob said there are more variants to the T-72 than can easily be listed.
You ask how many variants there are? Can you recite the letters of the alphabet? [whstl][clwn]
And the designation of several variants changed during the 1990s… that makes it even more fun…[8-)]
Yeah, the T-72 is definitely a mixed bag of nuts. Depending on which factory, which era, which country of origin; all of these factors played a part in the various configurations of this vehicle.
You may wish to check out this thread as well:
http://www.armorama.com/modules.php?op=modload&name=SquawkBox&file=index&req=viewtopic&topic_id=167913&page=1
During Dragon’s early years, they came out with a number of T-72 variants including the one with the cladding for nusclear blasts. Of course comparing them with the new models, details are found wanting. I have some of them and they look alright though. I hope come out with with new tooling of this series.
Er, besides the Tamiya kit, which is the more accurate base for conversions, there really are no ‘new’ model kits of the T-72 series of tanks at all, although they’re desperately wanted.