this is the final result of my setup. I managed a 2.19.215 with it on medium tyres. I also made some small mistakes here and there so I think a 2.19.000 is manageable. for qualify i suggest drive it with softs and low fuel load and maybe a 2.18.5xx will be possible (haven't tried it, it can be higher it can be lower). give it some time to understand the setup. be gentle with steering in eau rouge as it wants to oversteer a bit but it won't lose control. so don't be surprised and throw the steering wheel the other way as you'll spin out. also i must note, this setup is how I feel it works best for me. this setup might not work for you! if this setup doesn't work for you, i highly recommend trying all above setups as i also managed in the 19's range with them and also try the original setup as it still is very fast.
so here you go, try it and give me some feedback as i will also learn from it.