Yes, 50' should be way more than enough.
I did mine five years ago, on the bike, from top of header (at cyl.) to muffler. I did use SS ties, but I was also interested in looks.
Every couple of years I re-spray the wrap with the silicon wrap spray, to turn them solid black again. (White spots creep in, just like in the hair on my head).
Just follow the directions, and soak the wrap in water before applying.
