Smcka had conversion kits awhile ago at very good price. zetec bolts stright up to std gearbox. try to get manual zetec so your not chasing flywheel. you need to decide if going carby or injection. manifolds are available for bike carbs or DCOE/DHLA set ups. megajoilt is the simplest adjustable ignition set up for carbs, you can get the whole kit from trigger wheels in UK including wiring and Ford connectors to run std zetec crank and camsensors.
you will need a sump, water rail, correct waterpump rotation (depending on what belt system you use) starter moter depends on which flywheel/sump kit you end up with. price them up then look again at smackas kit.