My port side engine runs at 40-43 PSI at 3,200 RPM. My starboard runs at almost 50 PSI at 3,200 RPM. I wouldn't expect it to be exactly the same but I would like to see it a little closer. So I want to rule out the oil pressure sender and gauge. Looking at the parts diagram there are two different kinds of pressure senders. An "SS" and a "DS" and there is also a pressure switch that looks like it only goes with the "SS". I don't want to have to run down to the boat and take a look at it. Is there anyway of know what type I have without a physical inspection?