Sorry to be boring BUT may one also humbly point out the weight issue. The standard tyres are 8 ply and 'commercial', a ~ 2 Tonne van needs the appropriately strong rubbers.
It's good advice re the insurance Co. too .... don't give em any excuse to dump you should the worst occur
Ian
The Hulley's Bus 1989 2.1DJ Trampspotter LPG courtesy of Steve @ Gasure
They need to have a load rating of 94 or above to be ok for a t3, several car tyres exceed this but when the profile comes down so does the load rating.