[Blown Gasket]

This may sound like a crazy idea but when I worked I was paid to come up with crazy ideas. In my new "A" which is going to ship Monday I would like to have a temp gauge. I bought one about a year ago for my backhoe but never needed it. It's 12V and will not work on 6 so I thought about it and came up with this. I would drill the water outlet, not buy a new one and silver braze a brass fitting in it for the sender. Then buy a 12 volt sealed rechargeable battery, $20 find a place to store it, it's small. Then put a seat sensor switch in the drivers side seat so it was only on when sitting and driving. Now hide the wires as best as I can. Has it been done?