2003 Chrysler Van rear brake vibration since service

Thanks, I don't see the shoes being reversed, but will have the drums checked. It is hard to find a good machine shop any more or one at all.
The first set of drums I checked my self with a dial indicator and to the best of my knowledge seemed ok but I replaced them any ways to eliminate them as the possible problem.

I did check for leaks and contamination on the shoes. I did not see any.
I checked the function with the drum off by very lightly pushing the brake pedal while some one watched the action of the wheel cylnder.
All appeared ok.
Also checked the activation and release of the e-brake, this was ok as well.
I drove the van and slowed it with the e-brake and it vibrates just as bad.
It seems to me like a drum issue, like poor machining, but I am suspect of that because this is my second set of replacement drums and I am still having the problem.
I will try to have these drums checked at a machine shop tomarrow.

Thanks