Those tyres will have around 296mm diameter, don't know what you had before so can't give a lift but usually flipping the axle will give about 100mmm with about 80-90mm once it all settles down, while the axle will be 50mm spring packs size can vary, tyres don't give as much lift as many think either, if you can adjust your ball to that now you should be in the ball park to collect it okay then once you actually have it can fine tune it, I wouldn't be spending money on new shanks or anything until you have it in hand.................. I came close to shelling out $140 on new shank when I swapped over but I held off and flipping the shank was okay........... sometimes the paper facts don't match the practical............
I always take the measure from the bottom of the ball or ball cup but its never a mm precision thing 5mm either way is good enough.... besides once you have everything loaded you adjust things to suit so tug and van have the optimum set ........ also on your first run check your tyre pressures once they get warmed up and adjust for the right pressure. don't go by the compliance plate, once your tyres are warmed up on a normal 20-30c day they should be 4-6 psi higher than when you set them cold, if you have fitted P rated tyres they could be near the max cold pressure as well, with LT tyres you have more lee way for pressures.... the van will handle well and positive with the correct pressure and check your wheel nuts when you pick up your van, many a wheel has wandered off into the paddock because folk assume the workshop did them up.... not a joke happens often... depending on how far to home I would check the tension on the U bolt nuts when I got home as well............................. A ring or socket with a 10" handle would be fine, not so much untrusting but its peace of mind, well okay slight bit of untrust.
