I just posted this on the Foclajet Forums. Correct me if I'm wrong with anything...
Originally posted by me:
Let me see if I can help. (I'm guessing that you're the same person who posted in the Zetec forum on the CEG.) It would probably be nice to let you Focus guys know what Contour/Mystique/Cougar Zetec parts that you can use.
The pistons, rods, and crank are the same. Similar coil packs and wires, but some models had clips on the wires, others didn't. The oil pan is a one piece design that is shallower on the accessory end, deeper on the transmission end (opposite of the Focus). The oil pan and pickup are totally different from the Focus. I've been told by Tom (focus-power) that the main caps are all the same. The heads vary.
Pre-98:
-Hydraulic lifters
-EGR (no VCT crap)
-single timing belt tensioner (won't work with Focus or FRPP head)
-centered water pump (won't work with Focus or FRPP head)
-4-wire MAF with seperate IAT
-different oil pump design than 98+
98+:
-mechanical lifters (same as Focus)
-VCT (no EGR, you can tell by the funky cam gear and the taller valvecover)
-Timing belt tensioner and idler (same as Focus)
-offset water pump (same as Focus)
-6-wire MAF with internal IAT (similar to Focus)
-same oil pump as Focus
In order to drop a Contour/Mystique/Cougar into your Focus, you would need to swap over the passenger side motor mount/timing cover piece. That would restrict you to 98+ Zetecs. Either that or you would have to swap your timing/accessory drive from your Focus onto the Pre-98 Zetec.
Also, it is probably a good idea to stay away from a 95 Contour/Mystique Zetec. They used OBD-1 and some other funky stuff. The motor is the same as the Pre-98 though.
Ford Contour, son of the Mondeo, father of the Focus. 
I hope this helps.
