Looks like a great project. I have restored several vintage games with playfield changeover etc and you have to change the lamp sockets. You will never be happy with them and you will always have intermittent operation otherwise.

Pinball resource is best. Figure out the sockets you need and quantities and Steve will hook you up. He has all of them in stock. I don't replace the ground braid. Get some paste Flux and that will make the soldering much easier. Take your time and you will see the fruits of your labor.

You can certainly replace it. I never have and I have found it easier to utilize the original one and it has already been routed around all of the obstacles under the playfield. I trace around it with a sharpie before I remove anything then I can always look back at my old.playfield if I need to see which way the ground wire goes etc...