Adel clamps aren't the most fun but ganging three of them together is a challenge, even with Adel clamp tools. True, safety wiring them tight while assembling helped a lot.
The Van's instructions said to clamp the two wires separately to the engine mount, with a little "bushing" acting as a standoff. But the figure provideded showed only two Adel clamps -- a DG8 and a DG10, and clearly showed the two wires clamped separately. Cool, but unless you used one clamp to clamp the wire TO the mount, I don't see how this can be accomplished with just two clamps. And why would you want to clamp directly to the mount anyway? That seems to invite chafing of the clamp.
Enter a third Adel clamp -- DG7, which clamps to the mount, with the DG10 capturing one wire and the bushing to the DG7.