Inter / new Nacra tiller question

I'm thinking making some new tiller arms and crossbar for my 5.7. I don't like all the parts and pins in the original setup and would like to upgrade to the later tendon style connections.

What I need to know is the inner diameter of the tiller arm (or the outer diameter of the connector piece that goes in the tiller arm). OR the wall thickness of the tubing. I'm assuming the outer diameter in an inch.

Since it's completely a custom setup I will have to make my own tiller arms. Hopefully I will be able to reuse the tiller connector in a cut down form.

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Tim
Collierville (Memphis), TN
Supercat 15--sold :(
Hobie monocat--given
Vanguard 15--traded for...
Nacra 4.5--sold
Nacra 5.7
Hobie 14–sold to make room for...
Supercat 17–sold
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