Here is my revised angle iron set up.
The angle is held by three screws along the front side (facing the headstock). The other side of the angle iron is fastened to a square tube that clamps to the cross slide. The two bolts that normally hold the compound to the x-slide are not used.
Note that the angle iron was turned around. This helped solve a couple of problems. First it shifts the compound 2.5'' inches towards the x-slide which reduces the leverage on the mounting system. The mass of the set up is more centered over the compound. Second, it raises the vise by approx. 1'' which will allow more engagement of the compound dovetail most of the time.
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