Yeah, I've written about methyl orange in a few posts. It's a great titration end-point indicator. What I do is put a couple drops onto paper towel, then take a sample of the aqueous layer I'm examining (after it settles from mag stirring), and drop a bit of the aqueous onto the spot on the paper towel. If it goes red, then I've added enough acid to extract all of the amine from the non-polar...
This idea works well with other indicators too. (inc the ones made from red cabbage, etc)