There have been some folks that changed the ball joints to fully shrouded parts. But used the existing brackets. I think the biggest part of the job would be fabricating the base rod to ball joint bracket. I am sure that somebody that knows what they are doing and has access to a machine shop could do this. Same with the vise extension. You can buy the ball joints and rod stock for the arms so that is not a problem.
I wonder if, when all is said and done, you would save much money when material costs and time (personal and machine time) is taken into account.
Oh, and welcome. We will be interested in seeing what you come up with.
Here is a design that my friend Steve Pinson used. He used the existing slider and fabricated a piece to connect it to a ball joint. This is obviously much easier that duplicating the WEPS bracket.