Nice finds and nice to see someone else here from New Jersey!
Re cleaning an IHP, use a toothbrush and Dawn (or similar soap) to not destroy green patina. If you want to try and remove crust, soak in warn hydrogen peroxide in a small glass dish for a bit. The peroxide will dry the coin out so re-hydrate with some olive oil or better yet Verdi-Care.
Put them in a potato overnight. If they are really corroded you can try a mix solution of a teaspoon of apple cider vinegar with a dash of dishwashing liquid in about a half cup of warm water. Dont leave them in there for more than 1 hr. Gently rub off the excess crude with a Q tip