If it's anything like the Blaupunkt Heidelberg on my 90 Westy it will have 4
small holes on the front of the radio - one in each corner.  Get an old wire
coat hanger and cut off 4 pieces each about 4 - 6 inches long.

Insert a piece of wire into each hole and push on the wire until you feel
resistance.  There are little locking tabs that hold the radio in.  Push a
little past the resistance to release these locking tabs.  Then squeeze the
left pair of wires toward the right pair of wires and you should be able to
wiggle the radio out of the slot.

A good idea is to remove the ashtray first so that you can see the radio
underneath and you can ease it out.

Good luck

Rich