I like the idea of the ‘wrap around’ handle because it allows adjustment for balancing the light when loaded with either 4 or 8 cells.
A clamp-on handle also seems much more secure than a handle mounted to the shallow hole of the tripod mount.
I’ve done some searching, and found plenty of things that won’t work.
My GT’s battery tube is about 56mm or 2.2” diameter at the round section.
All of the add-on handles I could find are too small. Their designs don’t allow for much wiggle room.
Nitecore NHM10
50mm, 1.97” diameter
XTAR handle for S1 or D35
46.5mm, 1.80” diameter
MecArmy CL52
52mm, 2.05” diameter
JetBeam RM46 and MCH46 combo
46mm, 1.81” diameter
I thought an accessory clamp for motorcycle forks could play a part in fabricating a handle, but I couldn’t find any larger than about 50mm.
I’ve made sturdy mounts for my Meteor and Q8 using 50mm (2”) quick-release truss clamps used in theater and stage lighting.
There are a few 60-63.5mm (2.36-2.5”) truss clamps, but they’re the less-elegant non quick-release type. They are a bit larger than the GT’s 56mm diameter.
I hope my (unsuccessful) findings can spark some other ideas for a clamp-on handle!