Thanks for the input guys.
Had wheels off today and had a look. Everything seems solid still, no noticeable wear or movement from the components.
The full alignment was done straight after replacing all the components I mentioned. I had not been with the van for 4 years prior to that so nothing to compare it to really.
I replaced the 10mm spacers with the 6mm I had and will check if the weights foul the brake support arm, if so I will grind the weights back a bit and have them relocated next time I visit a tyre shop.
I am happy to adjust anything if you think it might help reduce this wear as it will quickly become expensive if I have to replace tyres at this rate!
Which component do you suggest adjusting and by how much? If I am methodical and measure the turns of nut and do equally on both sides should this generally keep things balanced?
I have also had someone recommend different tyre pressure and have been given a figure of 28psi up front and 31 in rear. I was told this was calculated from the tyre max load and usual autosleeper campervan weight, might this help?
In an ideal world I would just have it realigned but at 90 pounds a pop for the full alignment I cannot afford that regularly.