First post, long time lurker. I owned a 2006 328 a while ago but got rid of it because of life. So I finally am at a point to build a fun car. I bought a 1991 525I manual with a m50 today. The body has 300,000 miles engine completely rebuilt about 90,000 ago. The current plan is to fix up the engine to polish everything, fix little issues, and turn it into a weekend/track car. It's rust free runs strong, and shifts clean. I know it needs an o2 sensor from a scan I did and I think there may be a small vacuum issue, it stutters at idle. Is there anything else I should look out for or replace right away? I noticed some oil build up on the front driverside tubing on the engine. I'm looking to do the easy stuff myself but I am also looking for a solid mechanic in the Norfolk area I heard good things about eastern autowerks. Finally, should I just buy a new m50 to build up and eventually swap or work on the current one piece by piece?