Id go Zetec, use the std 2.o zetec clutch / flywheel and swap the sump for a modded Escort type(Mondeo) and water rail, Extrators from anywhere in uk, engine mounts can be made easily. Bike carbs or Weber 45's will see 160bhp , more power is cams/pulleys from USA, cheap, direct bolt in and they work great gets 185+bhp.
I have a built up Zetec which is good for 225bhp, though it will be running on LPG !!