OK . . . . . Ideally, a multi dimensional item such as this air boot, would best be measured some other way.

I was unsure exactly how to measure it, so please review the six photos below, and let me know if you might need anymore measurements that would prove useful.

Gerry . . . here's one more measurement that may effect the length of the boot you want to make.

The stock carburetor (installed) shows a measurement of 125mm from the reed valve bolt .... to .... the back edge of the carburetor's air horn, where the boot connects.

I don't know if your carb is shorter, longer, or the same, but this measurement will let you know if you need to add or subtract from the length of the boot.