I was considering doing the very same thing to lower my bags but I had a few concerns about cutting up the (very expensive) stock mounts only to find some problem with the clearances, etc. I was actually going to cut the ends off (as you did) and then switch them side for side and upside down so the geometry would stay the same. If you notice the lower arm of the mount drops down but also away from the bike.
I'm still considering doing it. I have no passenger seat or sissy bar though and I don't want the mounting bolts/brackets to be visible unless you are standing right over the bike. I working out an idea I had to make up some angled flat bar "straps" that would mount to the inside of the rear fender so you couldn't see them at all. Then I'd do the cut and flip for the lower mount, like you did !
One thing at a time though, I still have a 42mm HSR
to tune !