Sounds like ya got it squared away & your pressure differential makes me think of another guy on here a day ago with a similar gauge issue. The brass fittings to the right are 1/8" NPT fittings from the "Edelman" cabinet at the parts house. The "T" & nipple under it at the far left are 3/8" NPT but it is all I had left to photograph & the double female bushing is 1/4" NPT.