OH, Emma, YOU ARE A DEAR!! And a strong WOMAN to boot. Thanks for your support!
My father was terribly upset. But it was done and that was that. He never did tell me why he was upset, but I assume now (long years later) that first, he loved his adoptive father, and second, I could have taken Berg as my new last name.
Anyway only the RULES work here--following the German ORDNUNG. Bah Humbug I can say, but now I've done it, I'll let it stand even though it makes me uncomfortable. I came into my own over the decades between the end of Hilse and the beginning of the other 3 (yes, three) surnames.
The problems with Hilse? no one could pronounce it correctly, or spell it when they heard it. In classes, with the reading of roster, there were so many variant pronunciations that the speakers drew pain with every attempt.