There certainly has been some interest in this topic over the past few weeks. I saw a recent video on You Tube which I felt was promoting the unsafe use of those L shaped sling hooks without the use of a cross bar - and so wrote up an article on the matter (see
http://www.leylandaustralia.com.au - articles).
Others have also participated in the discussion and only yesterday was the topic again raised on a facebook page. It seems to me there are still those who suggest unsafe practices and so I have revised my article referred to above and included a stress analysis of the bracket and stud (see pictures below). What you are looking at is an analysis of the stresses in the stud and bracket when loaded by a typical power unit of 150 kg. The modelling is a little bit simplified in that the bracket is firmly fixed to the stud (as if it were welded), but even so, the results tell the story. The displacements of the geometry have been exagerrated to show where bending mostly occurs.
If you use those L shaped brackets without a cross bar, then the stress in the stud is some 10 times more than that compared to the correct procedure due to the leverage applied to the bracket. Even using the approved plate bracket on the outer hole raises the bending stress by a factor of about 6. In the case of no cross bar (sideways and vertical forces) the maximum stress is below (but in one case dangerously close) to the rated stress for the stud.
In the earlier pictures in this thread, the best ones are those which show a cross bar, such as Bill B shows, and the sykes bracket.
The rocker studs, if genuine, are adequate for lifting and moving the power unit in the factory on an overhead conveyor, but are not suitable for lifting the engine out of the car due to the lack of angle needed to clear the dash panel cross member. For lifting the engine out of the car, the sling brackets should be used with the hook bracket and the cylinder head studs so that the loading at the studs is as vertical as possible while also getting a good angle.
Just saying to someone that the head studs are preferred over the rocker studs only tells half the story - it is the cross bar support that is important as well. regards, Tony