old fuel lines and brake lines -Replacement Where and How? Tech tips please!

What old stainless lines? Mopar used mild steel. They never used stainless fuel or brake lines.
the old stainless lines i bought over a decade ago to route the brake fluid to my drums on my road runner. they used to store them in a tube in the autoparts store, we would pick out the length we needed, it already came with flared ends and two floater/sliding male screwin pieces