Oh, I'm not sure. My A600's A601 ram expansion just has some clips to unbend to open it. Not seen one exactly like that. Are the top and bottom of the shielding separate? If so could you just bend the top up and not need to desolder the joint? I'm wondering if that is like that to ground the ram card to the shielding...

BTW, the motherboard of the A500 itself looks in great condition. Nice purchase.