Dual-Carb Engine change

A friend of mine has a Jap import 1995 Civic 3-door hatch with a 1.3 litre carb engine.He is planning on installing a 1.5 litre dual carb or maybe even a 1.6 dual carb.What I want to know is if it will be a straight fit and if not will it require much modification?Will the wiring loom be the same and will the engine mounts have to be modified?
Also can a 1.8 litre dual carb out of a 93-94 Integra fit into this Civic and again,will the loom and the engine mounts have to be changed?Any replies will be greatly appreciated!