A thread on towing boats, hitches, et al...
may be of help.
Also, there was a thread a few months ago that initially showed a pair of white Xs putting their boats in the water via a steep boat ramp; that OP may have some good info too, though a quick search did not turn up the recognizable thread.
GL, mD
http://www.xoutpost.com/bmw-sav-foru...h-options.html