window regulator plastic clips

Hi friends, I have replaced my window regulator today and I found it pritty easy apart from the window securing clips that push over the sliders that hold the window up and help move it up and down. I bought 2 x clips from Renault and everytime I try and push them on they keep pinging off the sliders. Has anybody else had this problem? Any friends out there that can help me? It seems that the pressure off the glass is preventing me from pushing the window secure clips into place. I made a mistake by holding the window up with brown parcel tape and now that is left stuck all over my window and on some of my door panels, anybody know what I can use to lift the glue off that the tape has left on my door and window. It started off a good day and has turned into a nightmare of a job. Any help with either will be appreciated, thanks. I've been thinking does the regulator have to be postioned in a certian place so not to have too much pressure off the window preventing the securing clip to push on and stay on? Thanks again.:confused: