I was wondering what scapula position people recommend for this kind of shoulder stretch:

http://imagizer.imageshack.us/v2/640x480q90/41/grov.jpg
When I focus on protracting the scapula I feel the stretch more in my lats. When I focus on retracting them I feel the stretch more in my pecs. In either case I keep the scapula elevated as much as possible.
To me these two positions seem to focus the stretch differently, but I was wondering if anyone had insight into what scapula positions are best for this. My goal is to open my shoulders more for better handstand alignment and bridge work.
(Thanks to Vagabond for the photo demonstrating the stretch.)