I've made a spare wheel bracket that is strong enough to have a rack clipped over it to carry camping equipment, although the inside of the boot MUST be strengthened up and braced to carry the weight.  The rack is just put over the tyre and a tie down strap put around the whole wheel to secure it.

This boot rack is best for the monocoque chassis, there is an alternative lower down for 2B's

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As you can see, the bracket is fairly substantial. The 2 alluminium cones slip over the studs and locate the wheel, with about ¼" protruding, the numberplate bracket then goes on with a couple of nuts to fasten the whole lot up.

You will note that there is also a bright LED type brake light over the numberplate, this can also be seen when the rack is in position.

I have 3 rubber blocks stuck to the rear of the car to support the wheel, especially when anything is on the rack, and they also allow room for the rack to slide in place.

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