Might have to be the way!Don't know if it's helpful, but Pinball Resource sell bakelite strips you can cut and drill to make replacement plunger links
I looked into it and I don't think I have anything to cut that material with without cutting my own fingers offPinball resource won't ship to the UK anymore. I think Pinball Mania Andy can get stuff from him though so much be worth requesting it for his next order?
Use a Dremel no?
You could give it a go I guess. Don't forget your goggles and mind your fingers