WI Trudeau calls an election in mid-1978?

At the time his advisors begged him to do so, saying it would be the best shot before the Grits had their clocks cleaned in the October by-elections, being 1/15. He refused on the grounds that the Margaret made-for-Oprah saga left him in a bad emotional place for another campaign, and waited until he had no choice but to pull the plug, knowing he'd lose. So let's say he dissolves for an election in the first week of September, the Liberals win another majority.

Sept. 3, 1978

282 seats in the 31st Parliament

Liberal: 145 seats (+4)
PC: 105 seats (+10)
NDP: 26 seats (+10)
Créditiste: 6 seats (-5)

Incumbent Prime Minister: Pierre Trudeau (Lib)


My question is what happens now? Without the humiliation of losing to Joe Clark, does he pursue all the initiatives of the OTL fourth term or just continue an aimless drift with the exception of patration? Does Clark stick around or does Mulroney replace him? I think Trudeau might still contest the 1982 election, but step down in 1985 rather than 1984 as IOTL. Discuss.
 
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