Clearances round cooker hood over gas hob

[konfused]

Instructions for my 600mm cooker hood say it must be 750mm above gas hob.

But can I just slot it 750mm up into a 600mm gap between wall cupboards 470mm above work top or do I need to leave a wider gap between wall cupboards over a 600mm hob? If so how much horizontal clearance should there be?

 

[kirkgas]

if instructions quote 750mm above then they can be in line with the hob edges IF you fit them 750mm min above.