Rocket axle socket

Hi guys,
I am scratch building a Pitts S1 and am going to be using a sonex style gear leg similar to the rocket but not tapered. I was wondering if anyone was able to measure the thickness of the steel plate that is welded to the axle socket in order to bolt a standard axle too? It?s just so I can have a known starting point for what has been proven.
Thanks,
Sam

1/4" thick.

...and another idea if you are planning to follow the Rocket plans to the letter:

http://www.vansairforce.com/community/showthread.php?t=155984&highlight=Axle

Thanks guys I thought it would be 1/4? and thanks for the shim article.