Hey Anson,
Lead wiping was certainly an art , too much heat and it all ends up in a heap on the ground . With all the oh&s regs these days lead in any form is a no no . Back then if you worked with lead you were given a litre of milk a day, this was supposed to flush any lead that was inadvertently inhaled . I was taught how to "pop" dents out of a panel using an oxy torch and banana file.( i still have that file in my toolbox 35 years later ) . Some of the old school metal finishers that had been there since the early days could almost knock a dent out blindfolded. The production line pumped out over 200 cars a day and their were 3 dent knockers per side so each of us worked on every third car knocking out the low spots or filing down the high spots . The cars were wiped over with a water soluble oil , as they went down the production line they passed rows of fluro lights which highlighted the panel damage . Dents were marked with a circle and high spots with an X. And car body that couldn't be fixed on the line before going into the paint shop was fixed off line and a car that had previously been repaired off line took its place .