Does a peugeot 306 diesel engine fit a peugeot 206?

Probably could make it fit with a lot of work. Its not something i would do though, far too much to convert. As well as the engine you will need custom engine mounts, new fuel tank, fuel lines, engine wiring harness, engine ecu, display clocks. Upon this you have the fact that the 206 is a multiplexed wiring system with lots of control ECUs, so getting it to integrate with the older 306 ecu etc(if at all possible), would not be too simple. ALL THIS IS IF THE ENGINE AND GEARBOX EVEN FIT!!!! If you want my opinion, as a Peugeot technician for years, dont bother even trying.