The rails that go accross the roof rack have clips at either side to clamp it to the rack, does the cross rail fitting bow down towards the roof or upwards? I'm assuming that they go down towards the roof so the clips are at the bottom otherwise the weight of anything on them would put pressure on the clip.

And whilst i'm typing would anyone know where to get a clip as only the whole cross rail is available from Fiat and I broke one

Hi Alan I fitted the pair of fiat roof cross rails last weekend and they do hookdown under the roof rails and have a outer plastic cover with a key lock to clamp it to the metal hook. Halfords do a kit listed for the cross rails to fit to the Fiat roof rails and I suppose they will also have a extra kit for the lock set

Gina's got a spare set of rails for sale.....

I'll PM.