Thanks, Colin, I hadn't appreciated that the Eribas don't have an A Frame. The fairing looked as though it wrapped around an A frame.
I've actually installed a carrier in accordance with Aaron Calder's instructions, but I have developed a back issue and I'm finding manhandling bikes on to the Thule carrier to be a bit awkward (I've had the Thule carrier on the car for years). I think a platform carrier, like the Fiamma, will be easier on my back.
Mike - I saw the carrier you're referring to at AL's showroom and spoke to Cameron about it. It seems they only fit it as a "factory fit" on new vans, and referred me to Rose Awnings, but they can't get the bits from Hymer for older vans apparently.
it looks as though I'll either have to leave the bikes at home, or buy a couple of folding bikes and stick them in the van (a very expensive option!)