Recently picked up a used custom FL. Rifle is not perfect but suits my needs. It looks as if the frizzen is a replacement as it does match the browning on the rest of the lock and barrel, in fact looks like it was never browned, just left to darken with age. Would like to brown it but am concerned as the products I am familiar with require heating and I don't want to alter the temper on the frizzen. Anyone know of any products that work without heating?