NormK, it actually works the best I've ever seen (heard) with the modified carby. You're right about it saving the trouble of fitting your own. I'd like to find more of them for that reason.
In the event I need to install the nut and bolt, is there any compound involved? It looked that way in one of your pictures, where the bolt goes in.

Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!