A long time ago I bought a set of standard seat swivels and did some
welding and fabricating and installed them in a small boat , they turned
out great. Anyway I know there are a lot of size ball bearing swivels out
there to adapt into the vanagon seats. I have made a steel and aluminum
parts for many of my dirtbikes,trucks,trailers etc. I have alot of practice
with this stuff so maybe I will give it a try .Ps I am cheap , but I enjoy
trying crap like this .