Vintage crystal cleaning?

Hi OF
I managed to source an original crystal for my vintage 168.025 Connie. The packaging has true vintage vibes, unlike the modern plastic packages that protect the contemporary parts.

My question is related to cleaning the crystal. As the photos show, the crystal is quite dusty and may have some hair scratches. What would be a recommended cleaning procedure or best practice? I am thining to use an ultrasonic bath followed by Polywatch. Any objection against this? Thanks!

I just have it at home and it won't scratch the dial even more than it already is.

second this polywatch will be fine on its own