ok,so a bit of an update, i fitted a new connector plug to the CPS as mine had perished, things improved, but not completely, tracked issues to part of the loom, so was all stripped back, as there was rubbing wear on the rubber protective sheath, and 2 wires had worn through, so all were re wrapped, and then bound together.

next port was checking all the earthing points, i haven't done this since owning the car, what i found was under every earth point was painted surfaces, so contacts will be minimal. So as tedious and time consuming as re wrapping part of the loom, i undid all the earth points, removed paint, added come copper grease, re attach earth and cover in white grease to seal the damp out.

result appear to be much more consistant idle, no hunting at all, though still having issues from the breather set up i run, due to my original ford piece falling to bits....

new parts ordered, the whole crankcase breather set up can be ordered from the dealer still, though it is defo not cheap, but that in the pipe work as opposed to the actual pot itself....