I am looking into getting a single shot, switch barrel rifle made up on a Lawton 8500 action. The barrels are going to be in .339 Edge and .375 Chey-Tac calibre. Questions : Do the threads on the barrel tennon need to be lubricated to avoid wear and galling? What tension do they need to tightened up to? Can barrels be changed over without the need to remove the rifle from the stock? Will the scope need to be removed to switch barrels? Thanks for your advice.