Something is different in there, I have the red 3000mah UltraFires that fit in the GGT, I use them all the time, but got the covering ripped off in the GGTS. I do have an older GGT so the newer ones may be the same ID as the GGTS.
GGT was handmaded so the hole may vary a little. Telescope is very thin so I made it on a machine. That means that the 3000 18650 may fit to some GGT and not to others