My advice is forget it!! its a good idea, looks easy but there is a reason why so many people think about it but never do.

First choice is engine, 1.8 silvertop or 2.0 blacktop the 2.0 silvertop is hard to find. not as easy as it might first seem

1) sump. forget trying to use your cvh sump!! if you go silvertop then get the sump modified by g19 engineering or others, if blacktop then buy a new one from retro-ford and sell your cvh bits
2) water rail. the retro-ford one is very good but places both inlet and outlet on the same side, there is one that runs the other side of the engine (ike engineering?) have bought one but have not fitted it yet and you may have to fit a cosworth radiator
3) flywheel. if you get a silvertop then get it drilled for a rwd clutch or purchase one from retro-ford, blacktop the same buy the 1.8 silvertops one and get it drilled or just buy the correct one from retro-ford, do not bother with fwd clutches and extended release bearings etc and you will need a spigot bearing for any zetec engine
4) Alternator. had no luck trying to use the cvh parts so bought them from retro-ford
5) Fuel, Exhaust, sparks etc

I hope you get an idea that you either have to be good at engineering or be prepared to spend a lot of money and I have to say from personal experience forget trying to do it on the cheap and buy the parts designed for the job, just look at retro-fords web site add it all up and get a fright