Thank you for the respond. I found Oleson page and it is very
helpful with the drawings. Right now I am half way with disassembly. It was kind of painful to cut trough perfectly good and original leatherette to get to the screws. Well.
I was just hoping someone here did such a repair and have first hand experience to share. I gonna go with your pointer and sign up with www.argus.org
for more info how actually fix that problem. If successful I will report back.