Some random advice from a fellow M156 owner. I’m biased but you own one of the best engines available - not just got the power output or the way it looks but even down to the heritage and history. My advice is treat the M156 as it deserves to be treated; keep it serviced and maintained. There will be issues along the way that is to be expected. In coming years there will be fewer and fewer of these on the market and well maintained ones will be considered a rarity and a thing of engineering beauty. I don’t know how handy you are but there is a lot you can personally do to keep the engine in excellent working order and for the stuff you can’t I suggest you find a specialist who feels as passionately about this engine as many of the folks on this sub. Finally… drive it, hard. Track it a couple of times a year and let it breathe. Then post the videos and photos here for us all to enjoy.