A work basket includes a frame having a work platform mounted thereon to permit people to move about the work basket to position supplies on a highway surface from the vehicle on which the work basket is mounted. The work basket has an adjustable hitch mechanism to permit vertical positioning of the hitch for engagement with the hitch receiver on the support vehicle. A pair of outrigger arms mounted on the frame of the work basket on opposing sides of the hitch member is horizontally and vertically adjustable to position a foot member on the distal end of the outrigger arm into engagement with flat surfaces on opposing sides of the support vehicle to stabilize the work basket. Vertical adjustment of the outrigger arm is accomplished by manipulation of an adjustment screw positioned at the support bracket and by the vertical positioning of the outrigger within the frame member.