Code needed for Beta 5?

Hello,

about 3 years ago I sold my car without the original radio. Now I tried to install the radio on my tractor. Unfortunately I had to realize that I have given the code away with the car.
Perhaps you can help me.
Everything I could find out from the lables on the radio is:

VWZ1Z2A8512922
Blaupunkt-Werke GMBH
815 7649 234 360 1J0 035 152 F
Made in Portugal
Radio-Nr.

*014VWZ1Z2A85129228*

I know that there is a way to calculate the code, but I don't know how. So if you can, please help me.

Thank you in advance!!!

Florian Dachs