I have clems on a trellis, and I have hydrangeas planted in front of the trellis, and the clems grow into the hydrangeas. I have Limelight, Pink Diamond, Unique and Chantilly hydrangeas on the trellis.
The clems that grow into the hydrangeas show up well, so I would think growing a clem into a PG hydrangea would work excellent.
I'll see if I can't come up with a pic, but since I'm an iris grower, that's where I spend my picture taking.