I just finished building a test stand. It was patterned after the VMAR but that where the similarity ends. The base is 3/4" aluminum and the mounting rails are 3/8 aluminum. The rails will close down to 15/16" inside dimension and open up to 3 1/4" (one huge engine lol). On the bottom there are 2 10-32 SHCS's for side to side adjustment of each mount. Now I have to figure out something to mount the stand on and I should be good to go.