Hi Leslie,
I think if you're in any type of a flare, that type of adjustment would be unwise. I think a good chiro can do good work, but based on my experience, I would only see an "activator" chiropractor. The activator adjustments aren't as jarring and much easier to take. However, even with the activator adjustments, I find there is very little benefit if I'm spasmed through a flare.
I find that half happy baby pose is good at opening my SI joint. Think of it as an upside down runner's lunge.
http://www.fitsugar.com/275678I didn't start incorporating this stretch until things calmed down... When my piriformis was acting up early in the year, most things I tried made it worse.
Good luck finding some relief!
Freddie