It seems like a piece where a faceplate should unclip to be able to clean everything, but the darn thing is all one solid piece. So long as your orientation stayed clocked with that washer piece and the window switch actually clicks in, that should work perfectly for you.

I assumed that the slider piece was clipped in because mine didn't come out until I pried it out. It was actually just gummed up with a bunch of junk haha. Once that slider is out, you actually have decent access to the section where it clips in. I would suggest that everyone else did disassemble it fully as I did because the plastic could break prying on it from the top side.

I updated the photo album with pictures showing the disassembly of the L-R selector side as you showed in your pics, so thanks for that info.

I understand the process of looking at everything and meticulously trying to make it all perfect with these rigs we grow to love. It was the same for me and restoring faded plastic that turned grey over time. Once you see what a good-looking solid black panel looks like nothing else will ever suffice.

I have an extra 4 of those rear window switches sitting in the passenger seat right now. You lucked out with my timing of hitting the local junkyards haha! I'll try to successfully pull one apart for you, but they are incredibly easy to break. Depending on what shape they are to begin with really dictates if they will ever go back together again. The bright side of this is that they can be bought new online from China (actually really good quality too) for $5-10. I probably have close to 20 spares of them because they work on all 5 of the Toyotas I have (T4Rs, RAV4s, FJ80 LC and likely several other cars), but you would have much less hassle buying them online if you break one.