That was a great find Sapper. I recently swapped over a carbs and primer box from a discarded Rover onto the Briggs on a Victa that refused to run and now it runs.
I will now re -torque the two screws after seeing the clip in case I have over tightened them.

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