Turkish Mauser M1938 K.Kale 1942

[82Trooper]

Hello:
I have the chance to help out a friend with their deceased father's firearms collection. We are in process of sorting them out and going thru them to identify exactly what she has, cleaning them up and ensuring they are not missing any parts.

I believe this is a M1938 Turkish Mauser...manufactured in 1942. It is marked "AS RA" "TC ANK ARA" and "K. Kale" with a crescent/star. S/N is 110604.

Trying to research how to remove the barrel/receiver from the stock, for a thorough cleaning of the barrel below the wood line. I watched a few videos on line, and have removed the bolt, the trigger guard and the front barrel band/bayonet lug with no issues. But am stymied by the second barrel band which seems to have a pin/screw/nail through it. It appears to be peened over, and the design suggests it is not meant to be removed easily.

Can anyone share with me what is the accepted process to remove this and then reinstall it, with an eye towards keeping the original attributes as much as possible? Any insight you can offer would be appreciated. Thanks in advance.

Also..to remove the full stock, does the circled brass part (recoil lug?) need to be removed?