Get a power bleeder, it will save you a ton of time
Unless your current fluid is dirty and dark, its a bit hard to see when the fresh fluid has pushed the old stuff out. You may end up using more than 1 liter
there was a post a long time ago the approximate amopunts needed to flush each caliper.
Brake flush amounts
And yes, Motul 600 is overkill for a street car. ATE-200 and Pentosin (Pep Boys has it) are good choices