Tony, there's a T block on the port side of the engine block behind the alternator where the oil pressure switch sits, on our boat there is a spare port on that block that just has a plug in it. I believe that's where you would want to put the sender.

If you use an electric model (I wouldn't use mechanical on a boat too much risk) you could run the wire from it up to your panel in the cockpit, not simple but can be done if you have a fish tape. If you have the old style panel you probably can fit the gauge in there, it will be tight. But if you have converted to the newer style panel like I did there is no room for another gauge but you could put it outside in a small case of its own.

I would think you have to put it at the helm, if it's not there why bother even having one?

If you want to match your existing gauges they are likely Teleflex Red International series. I was able to get exact replacements for my voltmeter and fuel gauge (both were dead) from an online chandlery in Ottawa, I just checked their website and they don't list an oil pressure gauge though.

Here's a site that lists an Oil Pressure gauge (part # 53214P):

[URL]http://www.boatbandit.com/teleflex-red-international-3586.aspx[/URL]

25 bucks not sure if that includes the sender though might want to check on that.