My C4 has started leaking on both sides by the window and somewhere on the drivers side location unknown.I have purchesed a complete weather stripping set. How difficult is it to install?
Is it a do it yourself project or would a glass shop be my best choice?

It is not that hard just tedious, if you don't already have a weather strip install kit you will need one, consists of 4pc tool kit and as you know gasket adhesive in addition to adhesive will be needed. The front header w/two the two pillars and the rear roof w/sides for glass will take the most time as the channels will have to "cleaned", on these two I did not use cement as when I did the "trial fit" they were really tight. As far as the doors go, I had removed both panels to upgrade regulators but I think they will have to be remove anyway. Good luck.