Door track snail springs, safe removal & installation?

Hi guys,
I have some junk 1970 Duster doors & a pal needs the snail springs from the window mechanisms.

The doors & tracks I have are bent bad, so just sending him the whole track assemblies is out.

So I need to know how to get the snail springs out safely.

He needs to know how to reinstall them safely.

Any tips, tricks, special tools or advice please?

Thanks,
Barry

This one is from a Challenger, but same type of spring;