Help with extending acrylic tube on thrower

I’m after some help info with the extending acrylic tube on the thrower. I want to extent the acrylic tube with the green leaver on the thrower. So far I have aluminium handles which I have made to rotate using thrower chickens method on his v3 gun.

I have seen a few suggestions on the extension by rotating the handle by the info on the index section on here.

I have herd someone did it using a Toilet roll holder but can’t find any info on it. Has anyone managed to get it to work using the green leaver and documented it if so can you point me in the correction direction and how to do it.