So I've been reading my Fiesta (Mk4-5) Haynes manual and the Zetec SE engines (all with aluminium blocks) seem to be unrebuildable in terms of crankshaft removal. "There are no manufacturers torque settings supplied for the main bearing caps" and "it is not possible to refit the main bearing caps to the cylinder blocks using conventional tooling". Apparently the big-end shells are also "unusual in that they don't have any locating tabs and must be accurately positioned during refitting".

I've discovered that the rocker covers (ie silver or black tops) seem to be quite important. Am I right in saying that there are older "Zetec E" engines out there (with silver tops) that are different to the Zetec SE engines in the Focus, Puma and Fiestas? Can anyone shed any light on this please?

Oh and to put a 1.6 unit in as an alternative, after thinking about it some more from last night, I take it I would need a 1.6 ECU and key (with immobiliser chip) aswell, for the correct fuel/ignition maps?