Ford Bronco 351W oil pressure problem.....?

changed the oil pump...oil pump drive shaft...pan gasket and had just a great time doing it...now what should i start looking for a vac leak? if so what should i pump down to and should it hold tight and how long? my transmission leaks like hell prob have to add a quart every week or two, but my leak happens to be where the vacuum module gos in so....i guess all i want to know is im on the right track and has anyone played with a 351w with a C6 transmission