Welcome to the forum!
At this size, it is typically very hard to sex any cichlid as most distinguishing traits do not show until later in development (probably about 4-6 inches on a terror).
I agree, GT gender is much easier to determine once a little more size is achieved.
Having raised several GT's, it's been my experience that at 2.5 inches most males start developing abundant bright blue / green spanges. The females remain brown w/ minimal spangles like the pictured GT.
Here's a pic of one of my best male GT's at the 2.5 inch mark.