How to remove thru hull bedded with 4200

[BillWilliams]

After just re-bedding a plastic thru hull with 4200, I got a wild hair and decided to replace all my thru hulls (above the waterline) with stainless steel ones. They'll be arriving today from Boatfix and I was wondering what's the best way to remove the plastic thru hull I have bedded with 4200? What's the best way to clean up an residual 4200 from the hull?

Thanks