i would not go as far as saying you need to rebuild the engine mate.
its a bolt in affair if your going from n/a 4e to 5e
if you are turboing the engine depending on the size of the turbo you will need to either drop the compression a bit by either doubble layering the head gasket (this is the half ass way of doing it) or rebuilding the engine with either 4efte stock pistons or getting forged items.
what are you aims for the swap? more info you give the more we will be able to help. i also suggest doing a quick search as the topic has been covered so many times is not funny and there is some really good info out there