The T/C set triggers are not the best, so you might want to give consideration to replacing them. And the lock will already have holes drilled for the lock bolts. I'm not saying that hitting the same hole can't be done, but it's FAR easier to drill and tap a new one. If the gun is pinned, drilling a new hole in the tab is no big deal (same with the pipes). If it's keyed, you'll have similar issues in getting a good tight fit that draws the stock tight, so you might have to braze up the slot somewhat and re-cut it to get the fit you want. If there are estrucheons those can be re-used easily enough. You may well want to make a new muzzle cap though rather than try to fit the old one. Essentially, you are doing what most of us here consider to be a whole new build, rather than a re-stocking