i recently purchased a triple gauge set that reads coolant temp, oil pressure, and voltage. i got the voltage hooked up, but the temp and oil requires taking out a drain plug of each. does anyone know where i can locate both kind of plugs, or at least were i can find the oil pressure sending unit. its for a 289 engine for a 65 stang, it only has a oil warning light, not a stock gauge. can anyone help?