Here's a list of measured heights from wheel centre to guard lip (Hard Range is from centre cap upper lip on the wheel). Written as Front/Rear in mm.
Access Height
Gary - 455/475
Hard Range - 410/430
Keithy - 425/425
Low Height
Gary - 510/530
Hard Range - 480/500
Keithy - 525/535
Standard Height
Gary - 550/565
Hard Range - 515/535
Keithy - 550/565
High Height
Gary - 575/605
Hard Range - 565/585
Keithy - 580/595
Cheers
Keithy