My basic gear setup is the same for wrecks as it is for caves. The only couple of differences are the "accessories":

-undergarments: Almost always wear my Weezle Extreme undergarments unless the water is really warm. In REALLY cold water, I wear my cave fleece AND my Weezle.

-gloves: almost always unless really warm

-weighting: If I am in salt water, with my extreme undergarments and diving double 72's, I need to add a few pounds of weight. I do this by using Dive-Rite clipper pockets on my waist band, with 2 pounds of soft weights in each pocket. If I am in 85's or 95's I don't need the weight/clipper pockets.

-thigh pockets: no jump/gap reels in right pocket, but instead I have a lift bag and safety sausage. Primary reel in clipped on right waist "D" ring behind light (same as caves) and my safety reel is in my right pocket (as caves). Left pocket is the same with spare mask, tables and wet notes.

-surface sound signal: I use the Dive Alert surface sound signal. It pops into the wing inflator hose between the hose and the wing. Basically a (very loud) air powered horn to signal the boat.

-knife: in addition to the "z" knife on my waist and small knife on my wrist computer mount, I carry a larger knife in the knife pocket on my right thigh pocket. I am a bit paranoid about entanglements on wrecks and want a knife reachable from anywhere.

-goody bag. If I am after lobsters, I will hook a goody bag on my left waist "D" ring.

-ARGON bottle. For cold water. clipped to back-plate on left side. The bottle has metal clips, attached to bottle with line, so it can be cut free if necessary. Argon inflator is connected to dry suit, and back gas inflator is wrapped around argon inflator. This was I can switch to back gas if I have an argon failure.

-tank boots.  many boats will not let you on without boots!  

I haven't put it together yet, but I am going to be adding a surface visual signaling kit with a mirror, flares, dye marker and smoke flares (& VHS radio, GPS receiver- just kidding!). I am going to put this in a small light like canister, probably mounted on my left side like a light.

I think that's about it. I really try to keep all the basics exactly the same whether it is wreck or cave.

My gear setup for wreck diving is exactly the same as for cave with a couple of additions/exceptions

The major difference is that I attach a Dive Rite two zipper pocket upside down to the bottom of my back plate. I run two steel “quick links” through the drain holes on the pocket and then attach them to the holes in the bottom of the back plate. I use zip ties to keep the links in the proper position and stop them from digging into my back. Inside the bag, I always have a safety sausage, mirror, and a whistle and can add stuff as needed (cue cards etc). I have a 50lb Dive Rite lift bag rolled up and tucked into the straps on the back of the pocket (where the webbing should thread through if mounted on a harness). This idea came from a Great Lakes diver who recently moved to VA Beach and it works extremely well. I also lose the finger spools and move my safety reel off the rear d ring and into my right thigh pocket.

I also wear gloves when diving on wrecks and if diving a single Aluminum 80 (rare!) I add 2 Dive Rite quick release weight pockets to either side of my waist webbing with additional weight to offset the tank buoyancy.