Chris
I don't fully understand all the variations of these Webers, but it looks like that Volvo one has a wider barrel (venturi) at 32mm. I don't know what the DIR stands for and without looking at my Weber 30 DGF I wouldn't know if that one is a DFV or a DGV. The Panda 30 used a Weber 30 DGF but it might need rejetting to suit a BIS. Clear as mud?