As Bennie said it good but really lift, all terrain tyres (highway/roadies are utter crap in comparison offroad), power then either webber of EJ22. I wouldn't go with 27's on an L-Series personally as I think they are too big and would rub like hell aswell as stuff the gearing. 25-26" would be fine with 2-3" lift kit and better rear springs.
My 2 cents worth., I haven't done this though although Bennie does really know what he is talking about.