Well I have put a thicker layer of X23 on and now TAT reports 61 and 60 for 100% on both. Phew! But probaly still more improvments to go, I get the feeling that the ACF7 PRO does not put enough pressure on the CPU to get a good contact, hence a thicker layer of TIM is required.
I would really appreciat the experts telling me i'm doing wrong so I can get it right!