Hello. I have a shower cubicle upstairs that is glass paneled on two sides. The panes of glass are fitted into aluminium extrusions. One of the corner extrusions doesn't fit flush with the shower base, it is about 0.25in too high, leaving an unsightly gap that needs filling with sealant. I'm not sure of the make, or how it was initially assembled but I suspect it came out of the factory with the corner and end extrusions already fitted to the glass panels. I need to push this corner extrusion along the length of the glass pane slightly, how easy might this be? I suppose it depends on how they are intially assembled, if anybody could advise? Thanks.