Voigtlander Bessa lens repair

Anyone ever opened this specific one? And maybe done repairs? All seems ok, but the shutter is stuck completely open. Probably been like this for decades.

https://preview.redd.it/0cdecfqz636h1.png?width=1499&format=png&auto=webp&s=b47eddea23157c107ea762e5863988d762db344d