Gary says:
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Depends on the state, but generally it is not legal to drive with
something on the roof which extends beyond the footprint of the car.

You would need to slide the 2x4 back onto the roof when loaded.
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ROTFL! No, here in Canada we get to have all sorts of things jutting
out past the car's footprint. It might have something to do with our
British heritage: jousting and all, don't you know.... GRIN....

Yes, of course the 2X4 with be fastened length-wise.

Cheers,
Wilf
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