The most difficult part is getting Quebec to join in the Revolution. The British extended relative religious tolerance to Quebec, which led to some idiots in the 13 Colonies preaching that the Church of England was preparing to reunite with the Catholic Church. While this got the colonies hot and bothered (more so than they were already), it kept Quebec quiet, and I don't see that changing without some sort of protestant fundamentalist British Governor of Quebec.
IIRC (half-remembered from my old job shelving books at a genealogical library , reading a book I was supposed to be replacing

), the Quebec Act eventually or even immediately had an adverse effect on some parts of Quebecoise society. By imposing English law in place of native ones, many Canadiens thought that the British were simply replacing the despotic rule of the Bourbon monarchy with the (almost equally) despotic rule of the Hanoverians. The Act mostly served to placate the local gentry and clergy, and while it did this, the rest of the population remained apathetic to the British and were not motivated to fight for the British government. Some sections of the population (I can't recall specifics from this source, unfortunately) were even sympathetic to the rebels despite their Protestantism. So my point is that the Quebec Act was not the panacea that the British had hoped it would be.
Alternatively, Napoleon launches a successful Napoleonic Sealion and forces Britain to hand over Quebec, in the same timeline where Haiti is a prosperous, democratic ally of France and the cornerstone of Napoleon's Empire in North America. This prompts a war with the US (the US wants to conquer Canada, and Napoleon rules it) which pits Napoleon against Andrew Jackson.
The universe then disintegrates from the concentrated awesome.
First of all, Napoleon would win. Jackson may have been good at fighting the Indians, but in a pitched battle against the French Imperial army, I'm not so sure how well he would have fared.
Incidentally, the French regaining Canada could be accomplished in 1779-80. In
this thread I postulate that if successful, the Franco-Spanish "Armada of '79" could have taken several cities in southeastern Britain, forcing the government to the negotiating table. There "
the original plan then called for negotations in which London would be traded for India, and Portsmouth for Canada". Just food for thought.