Shoe Goo also works good on misc parts and recovering seat pans .You can glue the badge to the head tube once you have cleaned up the back so it fits snug and correctly. I used clear silicone and clamped the badge to the head tube with a piece of soft wood cut to the shape of the head tube. Silicone seals well and doesn’t dry hard and you could remove it when needed and clean it all off. Works great.
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