Hi Dave,
My 'van also exceeds the nose weight limit so I balance it by placing a few of the heavier articles from the locker into the 'van while travelling....not a lot because every kilo movedbehind the axle is worth '2' from the locker (not exactly I know). Normally it's the hitch lock, the jack and the power lead and I place them just inside the door and hem them in with the steps on their side - they have never shifted in transit and as they are items I take our of the locker on arrival (apart from the jack), it's no big deal to take them out of the 'van instead. I use a cheap Bosal nose weight balance to check the nose weight and it is suprising how much it varies - just having a full header tank for the toilet makes a big difference on our van with an end washroom. Good that you are taking nose-weight seriously - a lot of people don't and end-up with less stability as a result. Something else to look at may be your gas cylinders - there are light weight alloy ones available now for less that the price of a new car or 'van!