According to one aspect of the invention there is provided a mobile lifting assembly comprising a body frame with one or more wheels for transporting a structural member, and four individually controllable lifting devices connected to the body frame for repositioning (such as raising, lowering, tilting or rolling) of the structural member. According to another aspect of the invention there is provided a mobile lifting assembly comprising a body frame being adapted to locate on a supporting surface, a lifting device connected to the body frame for raising or lowering a structural member, and a skid resting on the supporting surface underneath the body frame and being arranged to contact the body frame to distribute forces imparted by the structural member on the body frame across the supporting surface.