Great write up!
If you are considering this, by far the hardest part is removing the old barrel and as stated in the article heat is your friend. Many are intimidated with a propane torch because overheating and causing heat treat issues is a big no no. 200 - 250 degrees is well below any tempering temp and easy to check with nothing more than water. Evenly heat the threaded area and use a drop of water to determine when to stop - water boils at 212f.
Degreasing everything also helps increase friction a lot.
Barrel torque to keep the barrel from shifting can vary a lot depending on how well the mailing surfaces match up. Mass produced rifles get really high torque above 100 or even 150 ft lbs to squish less than ideal machining together. Benchrest barrels on custom actions have won national championships with 50 ft lbs.
One thing I’ve found if you are searching on eBay for a used takeoff in a different caliber, is you have to search in a few different ways or the goofy search algorithms won’t show a lot of good deals. Of course search for “Tikka barrel”, but also ”rifle barrel” ”take off barrel” “takeoff barrel”. Look at every Tikka barrel that’s close or not just to see the other recommendations at the bottom of her page. I get the impression a lot of barrels turn up in abandoned storage lockers or estate sales and often someone doesn’t know what to call it.
Right now there is a 6.5 prc for $150, but 6.5 creed, 7 mag, 300 mag, 308, 223 have sold for under $100 - sometimes as low as $50-$60.
If you want a cheap good shooting rifle and have more time than money, buy two takeoff barrels in the same caliber, keep the best one, sell the other for what you paid for it, rinse and repeat until you‘re happy with how it shoots. Of course headspace differences need to be watched and accounted for.
For a switch barrel gun, just lube the threads with a little grease or antiseize and get a nice barrel vice that’s easy to use and fits well to avoid scratches. It’s not uncommon to have a monster barrel vice to take off factory barrels and another for installing/removing at lower torques.