with the Lovels, I have heard it is far easier to get your GVM upgrade drive in drive out
as they replace everything that needs to be replaced - and charge accordingly
you can do the GVM upgrade yourself
however
it is not an easy task, and you need all of the info required with you at the time (spring ratings, shocky ratings ect from the respective manufacturers)
and weighbridge certificates and engineers certificates and and and
I know of 3 people recently doing it , 1 to a 1996 4wd wagon, 1 was a 2007 ute and the other to a 2002 4wd wagon , all were pretty close to the cost of driving into Lovels and taking their product (however good bad or indifferent it is)
but the object was to have the suspension system they were happy with