there is such a thing as a projekt zwo slider track that makes the door open further away from the wheel but they are rare and expensive,i have heard of members unbolting the track from inside the van then putting a spacer in behind to kick it out a bit ie a washer or make a suitable spacer
I fitted a bodykit with wider arches and wheels that come out to a point on the spoke to a t4 a while ago, I got past the sliding door spacing issue by using penny washers. You need to take of the roller guide (long silver bit) and put 1 washer on the stud cosest to the door 2 on the second, 3 on the third and 4 on the fourth if you can. Doing this spaced it enough to do what i needed and is probably the cheapest option. Also for it standing up to the test of time... It aint fallen off yet!