Replacing 10-139 Shower Door Hook Bottom Guide

Step 1: Remove the old shower-door guide.

I can't. Detaching it from the DOOR was duck soup. Getting it out of the groove appears to be impossible. It would APPEAR that the originals were slid onto the bottom track with the end(s) of the track free. Now, of course, the track is sealed to the tub edge. There are ways to put the old guides aside or even remove them by cutting the track (if I do this, which end do I cut at? Near spout or far from spout?).

Bigger question: how will I be able to install your replacement? Maybe it's differently made from the original so it can be tilted in. Or maybe I'll need the cut discussed above to install them.

Or maybe you recommend taking the track off the tub edge and sealing it back on with your replacements installed.

Just DYING to know. In the meantime, I have another shower.