Wow I just caught on to what style of trac bar you were talking about suprarunner, listen to mike on this.  When I bought my 84 the toothless yokel that owned it before me had built a traction bar like that.  It was attached to the top of the housing and ran back to the crossmember for hte spare tire.  The crossmember was wasted!  THe rearend actually moves back on compression and forward on droop so the bar was trying to limit that motion and the crossmember gave before anything else.