if you are putting 2.0 zetec in your mk3 fiesta you will need from a 1.8 or 1.6 the following

sump and oil pump pick pipe as fiesta exhaust wont clear 2.0 sump

obviously you will need exhaust

water pump and pulley from same as 2.0 water pump turns opposite direction

alternator mount from block to put it on the front , although your diesel one will prob fit as will a cvh one

dipstick and tube from 1.8 or 1.6

wiring from engine bay incl ecu , this could be a bit of hassle as diesel will be different from petrol so not just a straight swap over

you will need some hoses from zetec fiesta or could make some of yours fit , somehow

flywheel from 1.6 1.8 zetec or cvh efi one and drill out holes fit , its already lighter so makes a small difference , done this on mine

inlet from the 2.0 is no good for your fiesta , too big but you will need throttle body off it or simillar ,

tbh its pain in the arse , would be simpler to fit 1.8zetec as it will come with the bits you need and will go in easier

there is more and if you need any more info i'd be happy to advise

john