The conversion ratio for the top 4 benzodiazepines is unfortunately fixed. Everyone reacts differently to Xanax, Klonopin, Valium, & Ativan. What we do know is that the two most difficult of these benzodiazepines to stop are the short acting ones, such as Xanax, and Ativan. The longer a drugs half life is, meaning after you no longer feel the drug to when the drug depletes out of your system is the drugs half life. Clonazepam has a decent medium to long half life. Valium (Diazepam) is the one benzodiazepine that has the longest half life, meaning it is the easiest to withdrawal off from.
Everyone is different. You are certainly going into the right direction. However, in my opinion you will need more of the Valium once it Is gone depending on your tolerance, which seems to be high considering your talks about Xanax. There is a guide called the Ashton Manual, which is exclusively handed out and followed in the U.K. It is difficult to be prescribed benzodiazepines in the U.K. and any benzodiazepine you are on will be switched to Diazepam to slowly taper you down. The key is to do this slowly, going down 5mg per 4 weeks. If you cannot handle it, you can stabilize and wait to go down again. However, never go back up because you will lose all of your progress that you just accomplished.
If you go to a doctor and ask for help in benzodiazepine withdrawal you should find a doctor willing and able to help you. America has deemed Clonazepam (Klonopin) as the go to medication to detoxify. However, Valium has a strength of 10mg, 5mg, and 2mg, the perfect dosages to detox from and it has a longer half life. Whichever one you so choose or your doctor chooses, do so as soon as possible.
I've been on benzodiazepines for over a decade. I only take them now to avoid a panic attack and I only take them because I need to, not because I want to. It attacks your GABA acid in your brain, the chemical that allows you to feel calm and relaxed. After years of doing this medication you will start to lose your ability to regain GABA on your own and it can take over a year for your body to start producing the doses it use to before you started Xanax or any benzodiazepine. I wish you luck!