As a mounting plate, from what I have read in te forum, you should be able to remove the mount from your existing Volvo radio and make a small enlargement of the rectangular hole to fit a newer third party unit. I understand the Volvo unit is held to its mounting plate by small screws.
Beware of buying a plate from an accessory shop. Some are LHD sold in the UK.
But playing cassettes now is a different issue.
