interior hanging signs

I have to hang some lightweight interior signs on a curved ceiling. I have tried two methods using Gyford parts, but they are not working for me no fault of Gyford). What I need is for my attachment to the ceiling to be able to swival 180 degrees, and so far I can only get an attachment to swival 90 degrees. this is for a straight rod, not wire.
Any companies that you know of that may manufacture this type of attachment. Im in a jam....

Need ASAP Thank you.