6 speed online is the only one i could find:
https://www.6speedonline.com/forums/bentley-42/
you won't find much info there though.. its a niche car and most people who buy them don't care about cars, just want to be seen in it. If you ask about modding its "well, why do you want to mess with perfection?" or if you ask about DIY maintenance its "what are you poor? just have the dealer do it".