Cleaning input selector

My Yamaha RX's have motorized input selectors. My RX-570, and RX-770 are about 8 years old and have some issues with the selector such as only getting one channel of input.

What's the recommended cleaning procedure? I have contact cleaner, but I am not sure how to apply it.

Thanks in advance for any help.
The input selector is motorized, and has some sheet metal/shielding(?) around it. There are some small slots in the metal where I could spray, but I have no idea, physically, where the actual contacts are in the mechanism.

Is dissasembly possible or necessary to gain access to the contacts?

Does it do any good just blindly spraying inside the mechanism.
As long as the hole can let you spray left and right, it's ok. You can spread it by changing sources after that.

Contact cleaner can't harm anything except the corrosion, dirt, grease and oil. Just be sure that the motor doesn't get some into itself. I don't think it's a big problem, but if there was some grease, there will be no more after that. You could spread some sewing machine oil/knife sharpening mineral oil into it after anyways.