The most protected part of the spring assembly is the front end from about 9 o'clock to 12 o'clock on the driver side (12:00 - 3:00 on passenger side). Look there for water based paint daubs around 9:00 (3:00) in pastel colors. If you can find some remnants of the paint daubs, carefully check to see if the underside of the paint daubs were adhering to bare metal or black paint.
The top photo has pink and light green paint daubs adhering to black factory paint.
The bottom photo has black paint on top of khaki and pale green paint daubs. The black paint was applied by a spring shop that rebuilt the springs. Close checking revealed the paint daubs were applied to bare metal.
If your springs have neither paint daubs nor any evidence of black paint, it's possible your springs came from the factory with no black paint. If you do find some evidence of black paint, you then need to figure out if it was put there by the factory or a spring shop.
(The pink and light green daubs are from an AAR 'Cuda, and the khaki and pale green are from my '69 Barracuda 340 - I took it to a spring shop decades ago.)
See:
https://board.moparts.org/ubbthreads/ubbthreads.php/ubb/showflat/Number/6504582/site_id/1#import
