>Well, with a plastic scraper, a screwdriver, and a wire-brush, it took me
>3 hours to clean up, oh say... 10% of the area. :( At that rate,I would
>have to spend *every* Saturday for the next 2 months, just to strip all
>that stuff. 
>
 In a nut shell... powertools! get an electric drill and various size wire 
wheels and a wire cup. The wire cups will rip off undercoating very quickly, 
then clean up with the wheels. Finally hand scrape, varsol etc. WEAR FACE 
PROTECTION, goggles and mask and hat, 'cause you get covered in rust+tar 
flecks. You need a reversible drill since the wires on the wheels/cup will 
slowly lean over and you end up flailing the surface. Reversing bends them 
back and gets a new cutting edge at the ends. Don't press too hard, you'll 
just melt and smear the tar instead of flinging it off.   sounds like fun, 
can I watch?  tim s.