I was going to recommend some new modern brake levers for the numbness and pain. Then I see you already addressed it.

I think your stem may be a bit too long. The bike is set up similarly to a Bianchi I have that's a bit smaller than I like. The seat height to bar height is not level. So, I'm bent over more and find my neck gets weak and sore on long rides. I prefer a French Fit on classic bikes. I don't see the point of riding uncomfortably. I am not racing.

Looking forward to seeing pics of your 'new' bike.