Options:
1) reinforce the tail gate, bolt a chunk of angle iron across the top, or maybe some plate across the back.
2) If you have the tools (an angle grinder and decent drill), you can bolt your own bumper and swing out carrier together. (Its less work to weld one up)
3) fold up your back seat and toss it in.
roof rack looks cool on the mall lot, but mine gets snagged at the most inopportune moments.