Hi, this is just an idea but in the CMP specification charts supplied by Geoff Winnington-Ball there is a section on weights and measurements for the various models.
it shows a front & rear axle ground clearance height.
what I suggest is you measure your height, compare it to the specification height and then get the spring maker to adjust to suit.
This is for cab 13 type but they may be (and I am not sure) very little difference.
Hope this helps
Cliff
