Curt mfg makes a hitch that bolts onto the back. It is limited by design though to ~2000lbs. More than that, and you need to mount to the frame. I think it ran around $120 or so plus shipping when I bought mine about a year ago.

You should also check your '92's tow rating. For my '95 LS its only around 2500lbs for the end mounted configuration. Should be about the same, but theres always a chance its lower.

As the previous post said, it all comes down to what you intend to tow.

Paul