Upper rear wishbones

I've been scratching my head with this one for a while now, and have come up with three designs, based on the following diagram;

The top blue box is the coilover bush and crush tubes, the lower one is the top mount for the MX5 upright, and the green is 5mm plate steel.

Design 1 (left) is the smallest design, but it leaves the coilover acting on the M10 bolt running through it, with potentially bending forces rather than sheer forces. However, this is how the Westfield mounting is done, albeit potentially with more than just an M10 bolt.

Design 2 (middle) gives more support through both, but again I wonder whether the combination of the upper mount and the coilover put the bolt in a bending position.

Design 3(right) is the belt and braces, this was my original design. No bending forces, all sheer forces. But is it too much.

Turns out that Westfield actually use two designs, one that is close to the first one;

And another that looks the same as number three;

To be honest, I think I'm leaning towards number three...