I don't understand why some feel the need to go to a larger than stock rear wheel. There is no gain whatsoever under 140 MPH.
The drawback is they will bottom out when susp collapses on the tunnel. Stick with stock dia.
If you run just the inner wheels the track flexes to allow it to tip easier. Could break the fiberglass rods if doing this, espically on a 15 wide track, however the rail width will still control this somewhat. Just don't want to land crossed up on the rear end.