I'm near positive just taking the roof off the clamps will be enough, they take up a lot of space, not to mention the stress creases they mold in the top for rigidity, they make the roof quite a bit taller. But almost for sure taking it off completely and putting it to the side.
A lot of my friends use the fiber roof for this reason, it's also quieter inside the buggy.
As for the tires I've done that, I don't recall but around 6 lbs or so, you don't want to roll them of course and if they are high ply you don't want to break the sidewall tread...use this method as a lost resort in my opinion. I've also done the changing tire method, as simple as it is if you go often that becomes a lot of work
But you got to do what you got to do. I almost think strapping down would be easier than changing tires...not to mention you have to haul them around everywhere taking more space and adding weight.
Please let us know what works I'm curious now as to the solution?