I found this while browsing around Academy - the old lady made me clean out some of my junk from the garage and I got ~$300 from returning stuff that I didn't need anymore. The only logical thing to do was spend it on bbq gear.
Its the Outdoor Gourmet DLX Rib Rack. Measures 14" wide x 9.75" deep x 6.75" high. I had to cut off the front handle because the LBGE thermo was hitting it. I also placed a piece of wine bottle cork between the thermo and dome to give some more room inside the dome.
It is the longest/widest/highest rack I have seen, and should easily fit 4 untrimmed racks of spares. $20 at Academy. I've been looking for something like this for some time.