Various questions about endless Ishapore 2A repairs

So a while ago I picked up a 2A and I love the thing. But it really needed some love. I got a replacement stock for it, as the original was oil soaked and spongy beyond reason, the draws being smashed, and this new stock is far too long. I've been removing material to fit but I'm already down to the plate at the back of the stock. So I'm wondering how to remove the wire screw at the back to be able to remove more material and fit this new stock. Should I just drill it out or is there a different trick?

Other questions I have are related to restoring the original stock and removing oil from it, if possible. The draws are a big concern for me and I'm not sure how to properly repair them. I've looked at the resources I could find but couldn't find it explained in a way that makes sense to me. Am I to shape them before putting them into the forestock? Or should I use files to remove material to shape? It's a process I'm reluctant to jump into without fully understanding.

I appreciate any help I can get! Replacing the draws has been my biggest hitch thusfar and answers regarding that could help a lot.