I have a 02 plate ford focus chic which has done over 130000 I brought it as i was told the engine had been rebuilt however this turned out to be false. Now the engine is dying and very tappety. It is sending oil to the spark plugs and have been told this would require a full engine rebuild.

I would like to put a new engine and clutch in there however i dont know the engine code. Also could i put a more powerful version of the 1.6 engine in there like a zetec s engine from the fiesta?
will it be a direct fit or will i need to replace the gearbox and all the other stuff on the engine.

thanks in advance