That's one of the jigs on my to do list Jim. I tried to make one from the edge guides that came with my 2 big Hitachis but one has fixed rods and they weren't long enough to use the part from the other one. I had to do a job just like the one you show and as careful as I could possibly be with the single edge guide I had a few very small strays off a straight line.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.