have a look here it can be easier explained
kaniewsky / All
i had seen this but a while ago and was not very confident in my ability to do the job once i had watched him using reasonable force to get the vents out... had a quick watch again and thought what the hell give it a shot.
anyway just done the job in no more than 45mins including having 2 brews (1C outside) and for someone with little or no skills or confidence in this area i'm quite chuffed.
for those with a MY07 cupholder onwards i did take out the vent and the radio but didn't need to, you can take out the aircon unit and attack from underneath, biggest issue is freeing the cup holder lugs but teasing and patience with my tools of choice did seem to do the job (slide them in just underneath the radio and try and tease down, its does require some reasonable force). PS the tools of choice are plastic wall filler blades (ie home decorating plaster filler blades). Picked some up from wilkos this morning, pack of 3 bright yellow for 98p and did the job very well, no damage to the dash or units.
thanks to all the help from the forum again - all in i reckon i have saved at least a hundred quid by buying the part 2nd hand and fitting myself. now just need to figure out how the missues has broken her laptop......