With a POD of 1945, keep Montreal the Canadian financial centre and the largest Canadian city. Hint: Unionism and Liberty. 
An accidental transport of the first Nuclear bomb to Toronto and detonation by idiocy destroys the city and makes Montreal the only city to claim the title.
A very surprised Harry S. Truman is dropped onto Nagasaki after wondering why the trip to Canada was taking so long.
![]()
Loi 101 was pretty much inevitable: the Unionists introduced loi 63 allowing freedom of choice in 1969 following the St-Leonard riots, which accelerated their demise. In 1974 Bourassa passed Loi 22, a diluted version of 101, and again with Loi 178 in 1988. Three of four passed under a non-PQ government.
The Anglo business community reconciling themselves to nationalist sentiment (the French fact) is plausible, vice-versa is ASB.
Another problem was the hysteria: Charles Bronfman said that "blood would run in the streets" if the Liberals were ousted. Bourassa I was like Rajiv Gandhi, lurching from crisis to crisis and winning due to the lack of a credible opposition: the Unionists were dead and the PQ was still embryonic. You need to keep the Unionists in power, but the only way to do that is for them to absorb nationalist and mild separatist sentiment- what Johnson Sr. did IOTL. If one party doesn't do that, the PQ is inevitable.
Part of the problem was that Duplessis controlled the system, but the system dated pre-WWI. Like Marcos' PI, this was a corporatist "state" with the iron triangle of business, Catholic Church, and government. Duplessis even exercised more control than Ferdie did in some ways: he controlled the papers via the price of pulp, personally phoning propreitors to demand "insolent" journalists be disciplined, etc. Not to mention controlling who U of M hired (PET) by threatening to foreclose on their massive debts. His press conferences were more like statements- along with your $100 Xmas bonus. He had the most nationalist creds of any premier except Levesque.
You need to keep the Unionists alive by Paul Sauve living to realign Quebec politics along left-right rather than federalist-PQ lines. Which means they might have to become a conservative PQ- what Daniel Johnson Sr. did IOTL. They have to absorb nationalist sentiment- which cannot be butterflied without major ASBs.
Taschereau introduced a measure in 1930 to create a Jewish board that would have provided for Jewish participation on the highest decision-making educational body in Quebec, the Quebec Council of Public Instruction. Some newspapers saw the move by Taschereau to revamp the confessional school system as an example of an undermining of Christianity. As a result of the opposition, the Jewish leadership did not push the issue when Taschereau was forced to repeal the Act and submit a compromise which he had the leaders of the Roman Catholic Church examine and approve beforehand. In the resulting bill, Jews were sent back into the Protestant system, and the Jewish board had no power beyond the right to negotiate a deal with the Protestant School board.