Yes, the Hairtail or Wolf Herring make an excellent trolling bait for Spanish. ( comment from a pro mack mate of mine )
How to rig them...... good question !!
I would probably suggest a gang of large hooks near the head ( 7 - 9/0's ) and maybe a stinger rig trailing from that to as far back as possible... maybe with a couple of trebles in the stinger rig ? Last treble in or near the anal vent of the Hairtail. Also using single strand wire for this... suggest around the 40 - 60lb.
Good luck.
cheers Phill