David,
But what would I plug that into? My current gauge, cable, and sending unit are one piece, and from what I hear, there is a liquid of sorts in there. I don't really know how it all works, but my guess is that the piece you picture (while cool) won't work for me.
Excuse the piss poor photo editing, but I'm tired. I was thinking something along the lines of this.
Oil in and out, and a fitting where I can screw in the special temp sending unit.
??