Philippe Mailhot wants the city to add a letter "M" and a "L" on either side of the cross on Mount Royal to spell out M-T-L.
"It'll make us all look at the cross and breathe new life into an icon that i think was somewhat taken for granted."
Mailhot, who has posted detailed schematics for his proposal on his website, said the idea is to make it a temporary measure for 375 days to mark 375 years of Montreal.
"Previous generations had Expo, had the Olympics, but 40 years has passed since the Olympics and we're ready for something new," he said.
The city is already readying plans for the 375th anniversary, taking place in 2017.
Last week, Montreal Mayor Denis Coderre announced $300 million has been committed to the celebrations and cultural institutions — including the Biodome, Jean-Drapeau Park and the Pointe-à-Callière Museum — will also benefit from some additional investment.
The Society for the Celebration of Montreal's 375th Anniversary is now taking public submissions for large-scale projects until Dec. 19.
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