I did Google I may have used the wrong search terms but I couldn't find any relevant information. I need to remove some fittings to replace a faulty regulator, using a Butane hand torch. I'm assuming I will need to clean up any gunk off the threads, before I reassemble, if so how do I go about doing this, Acetone, small brass brush? I'll be using low strength Flomasta liquid PTFE this time. Thanks.