The exact length of the decal is 170mm, or 6 11/16" from the tip of the 'T' to the edge of the 'H'.
See my pics for how they're positioned on my glossy black 2007. I stretched two strips of masking tape to act as datums - one across the centerline of the filler cap, and one 'underscoring' the "1050" decal, trying to keep them as perpendicular to the centerline of the bike as possible.
I held a steel rule under the bottom of the letters and scribed a line across the two strips of tape. That line passed through a point 6 3/4" from the CL at the front, and 4 1/8" from the edge of the filler cap at the back. Both of those measurements are true measurements around the curvature of the tank, i.e. I bent a whippy steel rule so it contacted the tank all the way around.
You can see from my sketch that the decals are pretty much centered about those two datums - 1/2" from the tape to the lower corner of the closest character.
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