Truck rear slider window seals

[TurboJ4000]

I just installed my rear window in the truck and the slider itself I think is sealed well to the body. But the seal on the actual panes of glass in the slider are not in the best shape. I know the window will need to come back out to fix this but does any one have any ideas on how they come apart?

It almost seems like it was welded together with the glass inside and has no way to come back out.

I could cut it apart if it came to that but Id rather not have to do that.

Anything I'm missing?