I built the chocks yesterday and assembled and tested them tonight. Right now I just
have it setup for one of the trailer. We will try it out and see if we need one for
the other side. Initial testing seems to show an improvement in stability.

I used 4x4 lumber that I had in my scrap pile. There are two pieces cut about 7 inches
long with 25 degree taper on each end. I used a 3/8" thread rod with jam nuts on one
end and a small piece of threaded steel plate in the middle of the other block. (I
cut the block in half, add the threaded plate and then glued the block back together.)

/Blog/PermaLink.aspx?guid=b5fe98f7-792f-43dd-986b-e06171411bb8

The link above will point you to some of my research notes. I will try to post a picture
when time permits.