HI thanks, I take all the comments on board and will probably stick with the original set up. As a matter of interest as Clasic Swede commented a gain of 3bhp with air box, In real terms how would that be felt in every day driving?

Unlikely that you'd be able to notice much difference beyond a "she's feeling lively today" similar to when the weather is a bit damp. Don't know how that affects you in Sagres! If the airbox is set up correctly with it's companion pipework and nozzle right to the front of the engine bay, it should give you a colder air supply to the carbs and that will help to combine with a tiny fraction of more fuel. Pancake filters will just suck in whatever hot air that's in the vicinity.
Using KF needles with the airbox is a good match. Better than the KD's which may be currently fitted.