I'd read about some UK guys doing this to get cheaper ammo.  I wouldn't think about doing it on a pristine or even a rough Lee-Enfield that hadn't been butchered but there are still some "sporterized" SMLE's out there that I'd do it to.

http://www.specialinterestarms.com/index.php?page=enfield_conversions

They have a basic do it your self kit for $160.  I'm interested in how rough a project you guys think this would be.  Given what the Fudds are charging for bolt action rifles in 7.62 X 39 mm it might be a worth while project.     

Hmmm, yeah, I'd have to round up some scrap steel and aluminum to make a barrel vise.  I'm not fond of projects that start, "Put receiver/barrel in bucket and soak with penetrating oil for two weeks. 

I've used the PB Blaster on my motorcycle.  I bought it used.  Of course those nuts and screws hand only been the bike since 2006. 
Some of those old military rifles have been quietly welding themselves together since WW II.

On gun barrel removal tools, search Brownell's or Midway for "barrel vise" to see illustrations of what they look like.  Same for "action wrenches".   There are a number of plans in books and on the Internet on making your own.  Trying to use a standard bench vise is damn near impossible on any piece of round stock especially if you don't want to mar it or avoid crushing if it is tubular.   In the Brownell's catalog you'll see a wide variety of tool/methods used to get barrels off actions.  You'll also see why for one shots jobs people make their own stuff. Midway had a Wheeler vise with wood bushings for $64 before shipping and handling and that is about as cheap as it gets.   On some tubes with severe contours or tapers, the best method is to make a casting  on it to get a grip.  In ye olden days I think they used lead to pour a two part bushing for those kinds of jobs.  There may be some better stuff out there now?