Doing it by the book there's quite a lot to strip out around the dashboard to pull the dash away from the bulkhead to let you gain access to the matrix. There's plenty of info on the internet, but I followed a you tube clip that showed a quicker way to do it without taking the whole dash out
In reality I got away with taking out the fuse box cover and the steel braces behind there along with the footrest and air ducting which let me see the end of the matrix. You'll also probabkly have to take out the centre console to let the dash move a bit
What I then did was got a ratchet strap (one with the hooks on the end), anchored it at one end and attached the other to the bottom of the dash and pulled it out to get better access to the matrix. (being plastic it will all soring back into place).
You then disconnect the pipes going into the matrix and it slides out sideways into the drivers footwell.
The biggest issue I had was getting the clamps off the matrix without rounding the screw heads. It's also easy to distort them and they leak when you put it back on. Warning - it's almist impossible to get these clamps. They are like a mini sized version of the exhaust down pipe clamps found on BL cars of the 70's and are not supplied by the dealer. I was lucky to get a couple of a disco being broken by Gemm at the time.
Even doing it this way allow a good 3-4 hours and a packet of plasters.
Hope this helps
n