Travis, in your situation, the live sand and rock was sitting in stagnant water for 6 months.
I'd recommend tossing all of the sand. Rinsing it is possible but would be A LOT of work and not really worth the effort. You can buy dry aragonite sand cheap and seed it with a handful of established live sand.
I'd totally dry out the live rock, maybe even bleach it, then rinse it well. After that process, I'd suggest re-curing it. There will be a lot of dead "stuff" on the rock that will kick start the "cycling" process. Make sure to use a skimmer when re-curing it, or LOTS of water changes.
If you're testing for Ammonia, Nitrites and Nitrates, you'll be able to determine when the cycle starts, follow the cycle and determine when the rock is safe to use.