Just tackled this job on my 306 with air conditioning and all I can say what a total pain in the ar$e managed to ruin the airbag, the hose going into the matrix and the linkages to the heater control, very annoying and frustrating job. Has cost me so far £200 in parts and two days off work. Still havent installed the new hose so the matrix is bypassed by a piece of copper pipe!
Its actually not that hard to get the dash out, once you've got all the screws and stuff out. Just make sure you use proper torx screws to get the airbag off because I ruined mine and had to drill it off.
Cheers
Ben
306 heater matrix
Moderator: RichardW