I've had good luck with Citristrip--paint it on, wait, scrape it off, re-apply. Some of the hardened bits are scraped off with a small flat blade screwdriver.
My can of Citristrip is in a real can. They may have changed the ingredients since that purchase but in TX you should have access to real good stuff for things like this.
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I don't do: disks, tubeless, e-shifting, or bead head nymphs. But I do hate all e-bikes.