"is it really worth trying to recycle 40 year old coils"
Hmm. This whole site is about recycling 40 year old bikes. What 40 year old parts do you think are worthy of use?
definitely tanks, wheels, forks, frames, brakes, pretty much anything that can be rebuilt, restored to as good or better than new!
but hmm shot wheel bearings? do you really try and 'fix' them? heck no grab some new ones and ride on...
same with a brittle leads/coil unit.
Its dangerous enough riding a bike..then add with just the one arm!
I need my bike running & handling good, and stopping better. Zero issues ditching the stock rotor, springs for new better parts.