It has something on the back to hold a catcher Jack, I might be wrong about the wider cut, I will have to measure it again.
I am not sure on the date, I got told once that it was a 1958 J.A.P and the engine numbers hinted towards 1958. Maybe we can find someone who knows more about J.A.P engines who can help us out more.
I am sure that Clyde must have been the maker, but just the fact that it was called Gardener and not Clyde made me think that it was made for someone else so when I say Clyde Gardner, I mean Clyde was the maker of the Gardener. (sorry about any confusion)

I doubt we will find the answer 100% for this any time soon, but for now I am happy.

Thanks for reading!