I have a 52 GMC Diesel and it has a huge 12 volt battery under the floor in truck. But, get this....the running board has to be removed to get it out of holder on frame side. Hole in floor is small as other trucks, no way it's going out that! Darn thing is 20" long or so at least, 10" wide maybe. Posts are at one end. Don't know what amps it's supposed to have, but I'm sure plenty. The starter on this things about 2ft long too!
Not sure if it's positive ground like the 6volts, gotta check that yet.
