Thanks for the info. I have a part of the linkage that hooks to the vent. It is short and curved with some ripples along the curve with a hole drilled in the ends. I used to have a 50 and it had a flat bar with a slot in the end and was 90 deg.with a short flat bar attached to the vent. Parts claiming to be 40-46 look a lot like my 50 linkage, in my mind, which is not the most reliable place to draw from. HA.
