Appreciate the replies fellas.
I should have mentioned the dipstick was relocated when the engine was out years ago as i also had to change the sump configuration to suit the chassi. Its been "Australianised" for lack of better explanation which means the sump is deep at the front of the engine and the dipstick is on the drivers side (Right) in Australia.
Oil pickup was something else that was also changed from US spec to suit new sump at the time from memory. I have to say there is nothing to suggest any leak from front of engine near dipstick or timing chain cover, but I will re check again anyway. I have tried 3 times running the car to temp on the stands whilst under it and it refuses to give anything away apart from a very slight rear seal weep, only apparent after car has cooled.
Have had manifolds off and cleaned ports when stuffing around with the PVC, nothing apparent there. Engine
oil is changed very regularly.
I have standard rocker covers with the only breather a rubber hose from where
oil can be put into the engine running to the throttle body. The car was fine for 18 months and it has just gone off lately, have only covered 5K in it.
I will keep checking and trying your suggestions that i can, if that all fails then its off to the shop.
Cheers
Chris