To finish it i cut the bolts with excess down to size, removed sharp edges and sanded any pen used in construction.
As this was a quick project I did not treat or finish the wood but think a gloss paint or varnish would look good if you had time.
In this picture hopefully it is clear how this mechanism works. As the monitors are pulled forward more force is applied, the distance between the diagonal pivot points increases which stretches the elastic creating a counter acting force to keep the frame in position. What ever sort of elastic material you use it may need some fine tuning, I think i was just lucky that mine was the right tension.