It’s actually a fair bit on a model seven. I have found a much faster way to do this...
Take the barrelled action out of the stock, place some decent tape that won’t wear off really easily. Place it back in the stock and just get the action screws started. Find some coarse emery cloth and you can work it back and forth up and down the barrel channel. This will take off material evenly, as long as you hold it correctly it will be a nice even space all throughout the barrel channel. As you remove material tighten up the action screws about half a turn at a time and after a bit you will have a perfect fit for a free floated barrel.