Joe,
i have extensively researched on how to do this,
and the install is very easy to do, however , the problems start with trying to find the right module to fit onto our pre 2000 cars, as the looms changed in 2000, just like the problems with the stereo units , and Jaguar dont do one.....
the loom picks up the feed from the boot accessory power outlet by the battery, then it hooks up to the sensors on the bumper by way of a module, the problem comes with connecting the module to the cars loom, as it needs a reverse light signal to turn on the sensors for reversing, and there isnt a connector provided for this on our cars.....
there is also a remote mounted interior beeper , again, not catered for in our cars..
you can always splice into the loom, but thats not desirable , its the same problem as trying to fit a tow-bar electrics, no universal connector...
there are two ways to do a pre 2000 car, splice into the loom, or replace the boot loom for a later type, but that may incur its own problems....
i aquired a full set of sensors for the back of my car, along with a loom for the sensors, a boot loom , cabin beeper and three different modules, but have no way of connecting them all together without making the interior look like a bowl of spaghetti ,
hoep this helps
BB