install of rear sunroof seal?

I am trying to install new sunroof seals on my 964 C4. The front is a piece of cake; however, on the rear (though easy to remove) I can not wedge the new seal in. Can someone give me a hint, or do I need to remove the headliner? TIA Ben

open the roof 3 inches, pop the headliner off in the front by gripping it with your fingertips and pulling down firmly and slide it into the pocket. remove the 8 small bolts and slide the 2 rear bolt plates inward to remove them, and carefully lift out the roof panel. it's pretty easy. don't take off any guide rails and leave the cables as is.