Well this thread just saved me, my window dropped and I discovered the broken guide clip. Called dealer and they dont sell just the plastic guide, they wanted $350 for the entire mechanism. Now I undertstand why they dont sell the plastic guide, as it cant be installed...what a poor design.
Thanks for all the excellent info in this thread and especially the link above I was able to 3D print the part. I then used a hybrid of all the techniques here. I drilled out the exiting post and replaced it with a 1/4 x 1 carriage bolt, a washer and nut...O and some locktite. I then used a dremmel to shave off the excess, added some grease and its now like new.
Thanks everyone for sharing.
Here is the results:
https://youtu.be/QNMZ6-q4Z6M