I would like to add a little something on the practices of Ithaca Gun Comapany on "Restoring" case colors on a receiver.
I do not remember exactly where I found the information, but it comes from the factory instuction manuals to the workers in the repairs department. It stated that from time to time customers might send a gun in due to wearing of case colors. Their method of "restoring" or touching up these colors was by irregular application of a cold bluing solution with a Q-tip.
You don't much more "low heat" than that.
I did not see anything mentioned about torches though.
