I have an old integrated cooker hood H450 X W600 X D270 which needs to be replaced. Having searched the internet, all the integrated cooker hoods these days appear to be smaller in height i.e. H380 X W600 X D270. A new unit will fit width-wise, but are they designed so the existing H450 X W600 kitchen facia panel will fit onto the front, or do I need to buy a new panel?