Yes it will fit
From memory i think yours is the EFI cast manifold (same as my fiesta) and like you say the airducting goes over the camcover, this in my eyes will heat the intake temps and like you say hides the cover.
By fitting the 1.8 inlet (I posume its off the zetec-e engine) you are changing the surface of where the throttlebody lies, so rather than being channeld over the camcover it simply goes around. If you have any probs with fitting it give me a shout!
It will make the car run lean, so if persistant on doing this try using a high octane fuel and see how it runs then