Removing peeling decals easily?

My friend has an 05 Montana with peeling decals. He has tried many different approaches to removing the peeling decals w/ limited success. Has anyone found a relatively easy method to remove the peeling portion of the decal? Any ideas would be welcome.

This seems to be a relatively common problem among Montanas in the 04-09 model years. We have been looking at used 5ers over the past several months and have seen quite a few Montanas with this issue. We occasionally see other models, but not with any frequency like the Montana, although I know it's no. 1 in sales so there are more of them out there.

Thanks for your help.