Here's a couple pics of a set mounted on 6 1/2" wheels:
They seemed to work pretty well, never had a push, but I also feel that has a lot to do with my front end set-up. Switching to 13x6.50 for the upcoming season, mainly because I'm curious how the difference feels.
Also, mounted, they came out to be around 11" tall, where some of the Carlisle 13x6.50's I've measured have been nearly 15" tall, so be careful if trying them out, that you don't come out too low.