Fat problem, please read!

Servus people, got a fat problem, bought a beta radio from eBay was in a (golf 4) new year of construction, wants to do that in my old Golf 2 because the tape has said goodbye! It just doesn’t work, talked to the pre-bestizer he says it radios 100 %, beta radio flashes also below, and if I set lamp people it too. MY QUESTION TO YOU! Do I need a DIN plug or any adapter that has part safe connection The VW consultant could not help because he has no idea! What can I do now, please help me! Maybe someone knows about it and can give me tips! Thanks already in advance!