Thanks for the replies!
340mag, you obviously are familiar with the product that I am asking about. I searched the web and found info about currently available auto body solder like that from Eastwood. I just don't know how the alloy of that compares to the same product from 50 years ago.
As an example, household plumbing solder contained a high percentage of lead 30 years ago. Now it is usually lead-free.
