I have started to do the minor derusting required on the floors of my son's '69. Thankfully it appears to be entirely superficial. I note that there is evidence that there might be rusted areas beneath the sound insulating material that is glued to the floor in specific areas (and also to areas of the tunnel). What is the recommended way to remove this stuff, ideally so that it is reusable (although I see Olof sells it for less than $20.00 per sq. meter, so maybe I shouldn't worry about re-use).
Aside from simply scraping, is there an easier way, say using heat? Anybody tried a hair dryer, for example? I toyed with the idea of using a small propane torch but I suspect I would regret that decision fairly quickly.

Thanks for any tips.

Barry