Antenna change Kadett D……..BITTE HELFT ME ! ! ! ! !

I recently bought a used Kadett D. Unfortunately he has a break in his antenna and I have to replace it. It is installed in the passenger’s code wing. Since I don’t have much money I want to save myself the installation costs that still get to the antenna. I have bought a universal antenna already. Only unfortunately I don’t know how to remove the old and install the new one again. That means, I can install it then already. Is certainly the same way, if I use the a Let me remove it. PLEASE WHEN YOU CAN HELP ME , HELFT ME ! Thanks for this already in advance . Your Fireball …..