and today, had a little look as to why oil pressure was dropping, verdict is that its not the oil pressure release valve, took the spring and ball out, no markings etc, shon a torch to the seat and no visable marks.
put that back in just incase crud had just been sat which i had just cleaned out.
symptoms:
starts fine, raises pressure to 60-70psi (as it always used to be just fine 'n' dandy)
as oil warms up, becomes thinner pressure drops. Now usualy if i were to blip accelerator pedal pressure would raise to the point till pressure is released and oil returns to the sump...except its not....its just staying at exactly the same PSI as at idle...it fluctuates a little maybe 5psi but that goes up and down unstablie.
hope its the pump rather than anything else i.e bearings on the crank
also when the engines cold it smokes blue from the exhaust, when engines warming it lessens (couldnt run the car long enough to tell if it desapears fully with a normal temp' engine)
soooo...if it is determined that pumps gone i can take the bell housing, fly and clutch and fly housing off while keeping the engine in the car and change the pump

i hope...if that still doesnt work im stuck