Got the connecting arm made today. First off I made a cardboard one. This was so I could get the curve right and length. I made arm in three parts. This was to allow clearance when third gear is engaged. Also allowed me to adjust length and position before final welding.
Everything seems to work OK, so next thing is painting.
Must admit I was lucky. Of the 1"x1/4" flat I had available, I only had 1" left over.