im sure that someone here will give PROPER instructions, but 1st time i did a double din removal i ripped out the thing under the radio just by force... after that the retaining clips on both sides could be accesed very easily.. im sure that there is a proper way of doing this, n if anyone else tells you anything different please try that 1st n my way as a last resort cus u MAY damage somethng when you try to rip it out...
best of luck either way mate...
oh and welcome to AGT
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ooh i just looked at the picture better
here is a better way
remove the two little plates on either end of the radio
behind you shoud see some holes about 2 - 3 on each side. this is the Ford/Mazda standard radio retaining mechanism. safest way is to go to a local auto shop, like autobarn, and get the ford removal tool for radios.. it looks like a U and there are two per pacage. you only need one pacage since its a single-din take the tool n stick it in the holes they match up to n push all the way in n the radio should pop out...
alternatively just take a very stiff coathanger. make sure its almost the same size as the holes. cut it and bend it to suit.. n use it as the ford tool same in the end jst leting u know that softer hangers wont work. ul need some of those solid metal ones that are thick, not those plastic coated ones that have like a 1mm diameter wire inside
best of luck
oh and where you buy the tool there must be harnesses. try northfeild, stratfield, autobarn, supercheap.. im sorry but i dont knowwhats there iin melbourne but thats what we have here
hope this helped at least a little