Gents:
I had contemplated making a few of these locking pins for myself, the wire is readily available, I don't know what the diameter of the adapters are on various wheel setups, mine are 2" OD.
I think in the next week or so I may purchase some wire and test bend a few clips. I do have two machines that are suitable for the forming so lets see what happens.
If it works and looks decent I will surely post my results and we can go from there.
I am thinking 1/8" diam wire, or possibly less, but once the wire is formed and the parts are heated and quenched it becomes very tough, maybe 1/8" is too thick, depends on the application.
I will measure the trial pieces on my chassis and post later today and if anyone has parts to measure that would be some good input.
Cheers
Phil