Cougar Engine Swaps

[Mesa]

Looks our 99 Cougar has a dead cylinder. The options are find a second hand replacement or tow it the wreckers.
Whats needed to swap engines between different year models? I understand the '99 2.5 engine with fuel return is different to non fuel return models (00-on) and may need the transfer of a number of components. Has anyone done the a swap using a later model Cougar engine or even a 3.0L swap? Any help would be appreciated.