How to remove a Fiamma Carry-Bike PRO C

Hi Guys?

I've read the fitting instructions. Its all pictures with no text explanation.

Am I correct in thinking that the two “C” vertical uprights are hooked on the top horizontal  cross bar fixed to the van and then bolted through the ends on the bottom horizontal cross bar? So the plastic ends have to be removed to extract the long screws to release the bottom?

Thanks

vintageb3