Whether you are upgrading or simply changing out of necessity, this guide should take you through the ins and outs.

You need your replacement turbo (this guide is for a 599cc car), a new exhaust manifold gasket/heatshield, 7 manifold studs (M6) and nuts (M7 for 698cc), 2 exhaust studs, 4 copper water transfer washers and an oil transfer gasket.

First remove the rear panel, shown here and remove the crash bar as well.

Remove the exhaust, use steps 1,2 and 3 shown here.

Next, remove the TIK. This is held on the the turbo end by a single jubilee clip, and the airbox end by another jubilee clip. Remove all of the breather and vacuum pipes from the TIK and just push out of the way.

If you want to fully remove the TIK you will need to go in through the engine bay (for better access) to disconnect the cycle valve from the back of the TIK.

So now it should look like this: 

Now remove the intercooler pipes for ease of access. This guide should be able to help.

Remove the upstream lambda sensor (21mm spanner).

Pull the small red/black vacuum pipe off the end of the turbo. It is cable tied on, but in reality it won't be held on there too tight, so you should just be able to pull the pipe off.

Using a 17mm socket, undo the lower banjo bolt for the water transfer pipe (this is where you will get an airlock later!). It will drain about 500ml of coolant from here, so place a bowl or similar underneath!

Remove the top banjo pipe water pipe, also 17mm.

Remove the oil feed pipes from underneath. These use a small 8mm socket.

Now you must undo the manifold studs (13mm), approximate locations shown here... you can (just) reach them all using a combination of extension bars and flexibility!

Depending on the age (running time) of your turbo you run the risk of turbo studs snapping in the block. The amount of stud on show will determine whether you have to drill and use a stud extractor, or grip the stud with mole grips.

Now the turbo is free, you need to 'simply' move the turbo out. If there are still studs in the block, you may need to just be a little more careful with the turbo upon removal, and you may find that the metal exhaust gasket gets caught in the thread of the remaining studs.... just persevere!!.

(The picture above shows the wastegate actuator still in situ; I chose to change the wastegate during this turbo change)

Use some fine grit 'wet and dry' to clean up the mounting surface of the block, just to ensure a clean seal when you refit.

Place a couple of studs in the block before you begin.

It was easier to place the turbo on the new gasket and feed them into place together, as this meant that you weren't struggling against the top heat shield with the angles etc.

Once located, tighten up the new studs and nuts (16Nm).

Reattach the banjo bolts for the water transfer (19Nm), reattach the oil lines from underneath, (8Nm), and reattach the TIK and associated pipes. Also reconnect the intercooler pipes, and if you had disconnected the electrical connection to the cycle valve - remember to reconnect that too!

Reconnect the exhaust and perform a test run

Now bleed the coolant system by one of two possible methods. You can either jack up the near-side front wheel, and run the car until warm or, if you have the opportunity, a high-revving run down a short road will make the water pump move the air locks quicker - this is a very effective method!!

Now reassemble the car, and keep an eye on both the coolant temperature and level. The interior heater is a very good method of establishing if you have an airlock or not - it will remain cold when the engine is warm.