A quick learner from Pennsylvania says:
July 13, 2016
Dave from SWISCO responded:
July 18, 2016
I agree, the 39-031 looks like a good match. When we started selling this operator, we asked a casement window company why they had an offset arm going down. Their feeling was that with the downwards facing offset, it would stay attached to the sash stud even if the clip became detached due to the extra pressure on the sash stud. Hopefully that makes sense!