The mixture control arm on the fuel injector was mounted so that it hung below the pivot. This meant that the cable had to run below the oil sump, which put it very close to the exhaust pipes. I messed around with it, but never came up with a cable routing that I was satisfied with. I then tried putting the control arm above the pivot, which was perfect expect that would reverse the direction of the control (i.e. it would be pull for rich, rather than push for rich) It turns out that the bracket that Van sells is actually a small bracket for the throttle cable, and a bellcrank for the mixture cable. The bellcrank reverses the direction of travel of the cable so you can run it above the oil sump. It is a bit pricey, but does a good job.

Here is another view of the bellcrank, looking up from below.