Removed rear plate.
 

It looks OK to me. No signs of water leak. But there does seem to be a burned look on the plate...

I'm thinking this will come off with a little wet/dry sanding?

Weak Springs?
 

I see no sign of water entering this side of the rotor. The seals all look OK to me.

But when I press on the side seals at the green locations, the seals bounce back.

When I press in the red areas, there is no bounce at all. Dead springs?

Only one of the corner seals moves at all. How much are they supposed to move?

If so, I guess this would explain smoking at startup?

Your side seals are stuck
you need to give everything a through cleaning and everything should be fine.
I would replace the side seals and springs in this situation.
Also get FD conner seal springs and thoughly clean and measure for specs.
Those areas where the side seal and conner seal meet often too out of spec to reuse.

Smoking at start up is probably worn oil controll rings it will seep past the side seals into the combustion chambers!

Thanks for the input.