Thought i better attend to the last real pieces of preventative engine work.
New coolant pipes under the manifold. They were the original ones which had done 290,000km, picture shows how they fail, they have 2 o-rings which helps and the rest of the pipe was fine. A chunk of plastic must of broke off one pipe, and when i flushed the system it made it's way into the heater valve which jammed one side open, unfortunately took a little nick out of the non replaceable housing seal but it still appears to work ok. BMW plastic truly is the a gift that keeps on giving.
Re-did the vanos seals as it felt like they weren't performing like they used to and was getting low rpm surging in first gear. Along with an adaption reset and its much more responsive with extra torque, and easier to drive with less clutch required.
Rebuilt the alternator with new bearings,slip ring and brushes for $50 in parts. The original brushes were on their on tip toes. A time consuming fiddly job but worth it compared to unknown 2nd hand one or worse, a dubious Chinese special that would cost hundreds.