I don't think the fitting can be any further forward it is fitted to the van using the Fiamma fitting kit. Here's a picture from when it was fitted and the brackets are from Fiamma and attached to the van roof onto slots already in place from Fiat (for roof racksThe brown signs on the surrounding roads are a bit of a giveaway there
I think you may have hit upon the manufacturer's escape clause - they'll probably quote some small print about angles and blame the fitter.