Mike,
I think you really need to decide what you are trying to accomplish. The dead shrimp cycling method is very effective for cycling a tank which uses a wet/dry or cannister/HOT filters for biological filtration.
If you were planning on running a full fish only with live rock (FOWLR) tank, then the wet/dry is unnecessary, as is cycling with the dead shrimp (the die-off on the live rock would provide all the ammonia necessary for a cycle).
Since you have the wet/dry, you really need to decide how much live rock you wish to have. No live rock is necessary - but live rock is a more natural environment for most fish, provides extra food (algae or small critters) for many fish, and, having enough live rock can allow you to get rid of your wet/dry (or turn it into a refugium), and probably reduce your maintenance (lowers nitrates, and reduces problem algae outbreaks).
I'm with those that say, however much live rock you wish to add (remember, none is necessary), add it all at once (now), or at least as much as you can. With a wet/dry and say 20-30 lbs of live rock, you could safely add several pounds of live rock at a time later on, with a very good chance of not overwhelming the existing biofiltration (and thereby causing a mini-cycle).
Less live rock = more swimming room for fish, so some folks use wet/dry filters without any live rock, while others fill their wet/dry filters with live rock (after removing the bioballs). In any case, if you choose little or no live rock, I'd put a single, small (1") piece of raw shrimp back in the tank to provide food for the bioiltration bacteria. Keep it there until ammonia and nitrite read zero and you're ready to add your first fish (if you remove the shrimp from the tank and let it run with no shrimp and little/no live rock, you'll be starving the biofiltration bacteria you waited to grow, and can risk having a cycle when you add your first fish if much of that biofiltration bacteria dies off).
FWIW, your wet/dry should have been running since the beginning - that's where you want the bacteria to grow, so not having it running just slows the process of growing bacteria there.
Good luck,
Kevin