One last question. My cousin said to bleed the line of all air, so oil is at the gauge. Does that make sense? I don't believe I've ever bothered to bleed the air out, and I guess air is better inside the gauge than oil. Which way works best? Does it even matter?
there is a whole discussion on that topic...
http://www.jalopyjournal.com/forum/threads/dumb-question-bleeding-an-oil-presure-gauge.31196/