I assume that this was a solo event (one vehicle as a time). I did that for several years, decades ago, as well as marshalling at regular ice races.
If I recall correctly, this Land Cruiser has the original transfer case. There were at least three different transfer cases offered (in various markets) in the FZJ80, and I don't recall if the details of this one were mentioned earlier in the thread; does it have a centre differential, or a viscous coupling for one axle, or is it just part-time (RWD or 4WD with front and rear output speeds locked together)? Without difference between front and rear axle speeds allowed, the vehicle will understeer badly on slick ice, and it would be faster in RWD.