Harris put Montreal up 1-0 at 1:57 of the first period on a shot from the point.
Mike Hoffman made it 2-0 at 4:18, and Brendan Gallagher scored a power-play goal at 12:23 to push the lead to 4-0 and end an 11-game goal drought.
Chiarot made it 4-1 at 18:23 with a power-play goal.
Mathieu Perreault scored at 3:55 to extend it to 6-1 on a one-timer, Jake Evans tapped in the puck at 6:08 for 7-1, and Christian Dvorak made it 8-1 at 13:21 for Montreal's second straight four-goal period.
Tyler Pitlick put the Canadiens up 10-1 at 9:51 of the third period, prompting a "Guy! Guy! Guy!" chant from the fans. Hockey Hall of Famer Guy Lafleur, who wore No. 10 for the Canadiens, died April 22 at the age of 70.
"I think everything he did inspires me, but a lot of people and hockey players, in general, should just always look up to a guy like that," Caufield said of Lafleur. "I think it's crazy that we scored 10 goals tonight. You can't make that stuff up, [and] everything happens for a reason."
Noel Acciari scored at 14:55 for the 10-2 final.
"That was cool, really cool," Brunette said. "I wish we didn't give up 10. … He was my dad's favorite player and a lot of people, that generation, was all about Guy. Too bad we lost him so early but what a hockey player he was. You don't find too many [Lafleurs]."
NOTES:Panthers forward Anton Lundell and defenseman Gustav Forsling dressed but did not play. ... Caufield has 23 goals this season, tying him for second among NHL rookies with Anaheim Ducks forward Trevor Zegras, Toronto Maple Leafs forward Michael Bunting and Detroit Red Wings forward Lucas Raymond. Hoffman ended the season on a five-game point streak (six points; four goals, two assists). … Canadiens defenseman Jeff Petry ended the season on a five-game point streak (seven points; two goals, five assists). … Dvorak ended the season on a five-game point streak (seven points; one goal, six assists).