shoulder mount for 1 focus puller
 

I just ordered a DIFocus v3 because it was on sale, and now I'm looking for a shoulder rig that I can hold steady, and rack focus at the same time. I usually work alone, so no AC's. It seems this would be difficult to move your hand from the FF to a handle without jarring it.
Currently, I use the mic handle that came with my Zoom H4n screwed in the bottom of my 7d, and have the strap pulled taut around my neck. I just pull focus manually with my left hand, and it works fairly well.
Here's an example:

I've done SO much searching, and it's quite overwhelming. So many rigs, so many configurations. I'd love to hear thoughts on 1 man cam operation, as this is my only option. Thanks in advance.

Zack