Thanks everyone - very helpful. The Mulfab 4/4 focus rad does look smaller then the current 4/4 / +4 / s1&2 Roadster rad. I will ask them what they recommend and whether a bigger core would be advisable, given I only want to do this once.
Another question - probably covered before - how do you remove the grille?
Keith - no the manifold is bare s/s. I had been considering wrapping it with heat tape all the way from the head to the cat. Another job that will probably have to wait till the winter.
