Thanks for all that Jungle Juice.
The WA Transport Dept has asked for a pre and post height to roof measurement.. that is why i have been trying to documented info. Anyway, i did some research and came up with the definitive height taken from the roof racks for most Sport, Classic and Limited XJ's in Australia.
http://www.rms.nsw.gov.au/rvd-pre1999/ lists the XJ height (from roof rack to ground) as: Sport and Classic: 1730mm and Limited: 1693mm. This explains the extra 1" for Sport and Classic models due to the Upcountry/Offroad suspension group. To back up these measurements, my Australian XJ owners manual lists the roof height as 1623mm (no roof rack) which is 64 inches. The roof rack is 2.75 inches which is 70mm. Add the 70mm to the roof height and you get 1693mm. To confirm these dimensions, JeepHorizons.com and Eric Zappe's Jeep Builders Guide Book both list the XJ height as 66.8 inches with roof rack. This is roughly 1693mm. The US models only had the Upcountry suspension as an option but we got the Sport and Classic springs which gave the extra lift to 1730mm.
Therefor, due to most Australian XJ's with trim level Sport and Classic having a roof rack height of 1730mm, i hope to be able to add 40mm to this with a suspension lift and 10mm with tyres to give an overall roof rack height of 1780mm. The engineer i employ has to inspect a variety of modifications on my XJ and i am hoping he inspects the modifications to the tyres and suspension, approves the lift to 1780mm (87mm lift for Limited suspension)(50mm lift for Sport and Classic) and i wont need a lane change test/engineering.
I have had a look at the ADR's for lights, and i believe my Protofab rear tyre carrier should be approved if i fit lights to it so that they can be seen at a 45 degree angle from the rear.
Slowly but surely i am working my way through getting the old girl into spec for engineering and licensing.
Below is a couple of pics of the Old Girl when i got the defect notice. She had a 6" lift, 35" tyres, 4.88 gears with ARB lockers, Protofab tyre carrier, Bushwacker flares, Acos, sunroof fitted, etc.. etc..