Well my trims sorted themselves out when I put the stock cams back in, actually all of my problems were fixed by doing that. I believe that the 272's which actually turned out to be regrinds were severely worn, I'm going to measure them in the near future to confirm.

As for the PCV system it still messes with the fuel trims when you pinch off the line but I believe this is mostly due to the airflow changing through the MAF, I think it is normal. I got my fuel trims within +/- 5% on the stock injectors / stock cams after I installed them and fixed a few very small exhaust leaks.