With the sissy bar on it will be hard to install a hard trunk on rack, I don't think anyone has posted pics of a hard trunk with the sissy bar. A few owners have installed the HD tour pack using the stock rack as a mounting point, but use back rests mounted on tourpack rather than bar. The mutazu (spelling?) trunk also seems popular.
For my 09R3T I use a soft bag that fits over the sissybar and straps to rack. It is very secure and water proof. Its big enough (with panneirs) to hold gear for 2 for a week. or 1 for a month - the wife packs a lot.