I didn't do anything with the engine for nearly 2 months when i first got it, I spent a lot of time trying to work out the wiring diagrams and how to fit it in the 205 with out having to tilt it too much. I booked a week off work and started to dismantle the 1.6 with allot of help from my Dad. After a day the engine bay in my 205 was empty. The bumper, valance and radiator was removed so that the crane would be able to lift the engine upwards through the engine bay. The drivers side of the dashboard was also stripped down so the wiring loom would come out in one piece still attached to the engine. The only bit of trouble that we had was the bumper bolts inside the wheel arch were rusted into one lump and after 1 hour of tightening and un-tightening decided to snap. Also the 406 engine comes with a fixed position alternator and an adjuster wheel which slackens or tightens the belts. I didnt like this so I took the adjuster off the 1.6 engine, cut it 1/4 of the way along so I had a mounting piece and a adjusting piece. Then welded a 1" square piece to the mounting to extend it downwards. In this extension a hole was made and the adjuster was attached. The alternator lost its bottom mounting point and we out the new adjuster in its place. Have a look at the pic on the left to see what I mean. 

The next thing we did was trial fit the 406 engine in the engine bay. It went in using the 306 mount and the other 2 mounts lined up ok. The two main problems where that the brake servo was being pushed up nearly 1.5" and the radiator would not fit in its original position because of the inlet manifold.  Out came the engine again and we began to swap the gearbox's over so the original 1.6 box would be used with the 406 engine. This also meant the flywheel sensor had to be made fit. It goes on the top of the gearbox where there is a teardrop shape casting which wasn't machined in production. I tapped a thread into the smaller hole and then had to use a hand file to remove around 1.5mm of aluminum around the edge of the large hole to fit the sensor into. The hole had to be square so as to keep the sensor in the middle of the flywheel. It took bloody hours but eventually it fitted nice. We put the gearbox onto the engine using the 406 clutch and the 205 release bearing and bolted it up again.

Out came the drivers side engine mount next to be cut down. My Dad pulled the shaft out of the rubber as it is only glued in and cut 1" off the top of the mount. The shaping had been lost a bit so he heated the shaft with a blow torch placed it into the mount and squashed it in the vice for an hour or so until it had cooled down. Once cold it was glued with an epoxy resin and left set in the vice until the next day.

In the mean time I was working on moving the radiator out the way of the manifold. I didn't want to drop it down behind the beam at the front because i've heard that with the bumper and valence in place the car can start to overheat, I don't want that as im planning on abusing the throttle pedal when done. So instead I made two brackets out of angle iron to fit on the front of the car and stick about 4.5" out further than where the radiator normally sits. A thick tube was welded between the brackets and the lot attached to the front of the car. I cut a hole in the front of the car so the hose for the bottom of the radiator could be attached. 

Got up early in the morning again which I was getting used to now :(. to start and put the engine in. The mount was released from the vice and was tested by doing a nut up to the correct torque, the shaft didn't move so we fitted the mount back on the car. Next up was to get the engine in and lined up on the mounts and also the exhaust downpipe. The engine was swung in and as it was lowered the exhaust downpipe bolts were lined up so we could see what angles needed cutting in the downpipe to make it fit. With all the three mounts tightened up the brake servo was just being missed by the rocker cover, and the gearbox linkages lined up ok. After looking under the car we saw that the downpipe only needed lifting less than 1" to make it fit the exhaust manifold so all was looking good.

The slam panel which still had the radiator and cowling attached was rested in place at the top and the cowling fitted to the new bottom mount. The top hose that goes to the expansion tank fitted ok. The other that comes from the 406 block needed cutting and stretching a little as it has a dodgy connector on one end and a spring clip connector on the block end. At the bottom of the radiator the thermostat was wired back up, and the bottom hose which now goes through the bodywork was fitted onto a new metal hose which a guy at work gave me the day before I knew mine had sprung a leak.

A quick trim of the bumper because the cowling protrudes a little is all that is needed for the mechanical side of the conversion, its just the electrics which are left now to be wired up before the car can be ran.