Possible Clues:

• Imagine 3 down holding up the Liffey Swim, for instance
• Imagine engineer holding up the Liffey Swim, for instance
• Imagine film unit in The House giving it one's best shot perhaps
• Starts 18 across with support from one of those holding up the Liffey swim?
• Icon to plant evidence locally, as it keeps Monet's women in the garden in one place
• Home hang-up
• Icon to plant evidence locally as it keeps Monet's women in the garden in one place
• Painting's mount
• In which one may have got shot
• Oil container #3