Were you able to find one? I don't know if this is too late. But, if in case you need some info. I got a research online about it  and here are some references that will probably an answer to your inquiries. Please refer to the links below:

[url:1h56rqo6]https&#58;//issuu&#46;com/fbcpublishing/docs/160310204504-8428987d8ca04e82a0e3d86ec6dd8b94[/url:1h56rqo6]
[url:1h56rqo6]http&#58;//antique-tractor-parts&#46;steinertractor&#46;com/tractor/13&#46;6-28-Tube[/url:1h56rqo6]