How come you need the sump etc? I thought the 1.8 was the right sump for mk4 so the exhaust still passes in the right place.
Have a quick check in Haynes manual etc about the loom and ECU, it'd be handy if they both used the same type ecu, but i doubt it very much. Havent looked at the loom in too much detail on my EFi as im trying my best not to think about swapping the engine. Safest bet is to get engine loom and ECU with the engine, then splice the right bits into it from the MK4 loom, that way all the plugs/connectors are in the right places and it'll fire straight up. You should only need a few power wires from MK4 loom to the mondeo engine loom.
Theres a few guides about it on here too im sure.