I am not sure but Robison in new england of the USA, has I believe used the Arnage gaskets on turbo R, even before there was any shortage of gaskets. He has a website and has articles on the subject of turbo R and why the gaskets fail and what to do about it. (how to fix it up in your own shop, or write a cheque for $30,000 and then pray).
Use your PMC for mental therapy. I replaced my psychiatrist with a PMC. Thirty minutes of driving per day is more effective than doctors and drugs.