Hmm... I only got one in there, and I had to lift her over the back seat, but it worked.
I've also managed the 42" LCD panel in a box. That was scary-tight. It was lying at an angle against the backs of the front seat. But I had to make it work, because the guys at Best Buy were taking bets on it not fitting.
I also tried to buy 3'X8' sections of gridwall. I thought I'd just lash them to the roof rack. I got them all the way out to the VX before I realized that I didn't actually /own/ a roof rack...
That was dumb.