Nissan stx 2013 v6 suspension upgrade

[gomer]

Hi I wish to upgrade my suspension for towing and extra clearance for a Cape York Trip nothing to serious though just light 4wding. Have a bit of weight on the back long rang tank ,canopy, slide floor,fridge,tradesman roof rack and the back full.Already have bull bar and winch. when towing the van the ball weight is already up there at about 280 kg.Will drop this off at Cairns and pick up a 4wd trailor. The ARB guy recommends this below at $2400 will this do the job 20 to 30 mm extra clearance front and 40 mm back and 400 kg on the rear end.

http://www.oldmanemu.com.au/old-man-emu-suspension-selector

Thanks for any help