GT Zaskar -- how to tell the different models? And sizing?

Is there a code in the serial or other way to differentiate between a Zaskar,
a Zaskar LE, a Zaskar Expert, etc. (leaving out the carbon$). Or is it only a
decal thing?

With a non-traditional (ie, slanting) top tube, what is considered medium,
large, etc. I've heard that an 18 inch seat tube (measured from c. BB to c.
TT) is large. True?

Thanks.

Another Q:

Are the Zaskars front-suspension bikes? I've read many reviews (mostly at
mtbr) but most of these owners say they've modded them, so it's hard to know
what was on them when they were new.

Did/does the Zaskar come with front suspension?

Visited the GT Bikes web site but they're pretty slim on history of early
models.

Is there a web site of photos of GT Z's?

Thanks.