Purchase a pair of extractor Keys (available on Ebay or from Halfords or similar).
It is possible to use four pieces of wire coathanger or small screwdrivers or small allen keys. All 4 must be inserted at the same time through the 4 small holes on the radio front .This will release the 4 spring clips.....and at the same time the radio has to be pulled out. A fiddly job where an assistant is useful
RegWorts
June 2008