I picked these up on Ebay a while back. They are in my 62 Baja, the ones I made for it 20 yrs. ago never held up very good, couldn't handle the torque twist. The spring plates are a Thing only item (maybe) I ended up making my own using 1/4 in. cor-ten steel and cutting the splines from a pair of old spring plated.
Ken
Thing reduction gear adaptors pics
I wish you the best of luck but I snapped both 1/4 inch Sway-a-way spring plates and drove both rear tires under the torsion tube on my old Baja. It took a 4X4 with a winch and a trailer to get my Baja out. Never another Bus reduction for me, IRS is so much better. You not only get the gearing and the ability to run really big tires but longer travel as well. And best yet no obnoxious torque reaction unloading the tires when you really could use all the traction possible. GDRBO