You don't need a jig, nor a specific frame table.
Even Jimmy Long (who seems to have some sort of saintly reverence by some)uses just a conventional rack with simple hydraulic jacks.
It ain't rocket science, but it does take patience. There's a great description of the means of determining alignment in the manual, and a little common sense about where to put the pressure often results in the frame's own "memory" returning it to straight. (That's why you avoid heat at all costs!) Often a simple turnbuckle from the farm supply is enough to pull a downtube back in line.
Harley frames are a piece o' cake to straighten. Try an Indian or Henderson (Schwinn) frame some time!