Best way to cut stainless steel cooker hood

Hi all
We decided to try and cut our stainless steel cooker hood yesterday. Due to the low and sloping roof we only really need to use the one section of hood and a very small insert that slide into the main body which is the good part which is on show

After reading bought some tin snips to cut the metal that you wont see and while they did cut well they also bent the metal out of shape so as we have to cut the main (on show) chimney it was clear that tin snips wasn't a good finish for the...

Best way to cut stainless steel cooker hood