There is really not a practical, non-damaging place, where a Hi-lift jack can be placed on a ZJ. After market bumpers or rocker protection is needed.
Some have found the Hi-lift works out ok if you place it in the rear hitch. Hi-lift also makes a bumper chain type of attachment that you may be able to get to hook onto your front tow hooks. The best thing to do is purchase some rocker protection, and/or front and rear metal bumpers to place the jack under.
If anyone has more information or pictures, please contact josh@jeepzj.com
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