The braze-on is attached at a very specific angle in three dimensions, so I prepared some jigs. Here I'm using a tool that allows me to maintain two of those angles. One of those angles is defined by placing the blue body of the tool against the other pulley block and the blade in line with the Bowden cable entry, whilst the other angle is defined by adjusting the blade angle to match the pulley block angle. I also needed a shim to set the angle between the surface of the bench and the top face of the pulley block. And this reveals one of the reasons I chose to use JB Weld steel reinforced epoxy to attach the braze-on. The pulley block is plastic, so it would have to be removed for brazing. With the block in place I had something to provide reference planes. Other reasons for my using JB Weld are that it gives plenty of time to adjust the angle precisely, no damage will be caused to the powder coat, and it does not require brazing tools. Of course one could offload brazing on to a good local bike shop, but if they get the angle wrong it's game over.
