I think Schmautz took over the Mckenzie role after Mckenzie jumped to the WHA. Cashman was regarded as one of the top fighters in the league and the bruins were really big and strong on their top 2 lines with Hodge, Espo and Bucyk. Not fighters but really big power forwards for their day. Vadnais could take care of himself. O'Reilly was coming on and would make himself into a top fighter
and player. Looking back at the entirety of his career, he'd be the Bruin I really admire most.
Of course, later on they added fighting from Secord, Wensink, Jonathan. They swapped out
Andre Savard for Pete McNab who was another big body who could play.
The Flyers were team tough. I've written about Schultz and his role, but basically the team went like this . . . nobody touches Clarke or the whole team would come after you. Their bench was their enforcer. Schultz was the instigator, Kelly and Dupont could take care of themselves, Saleski really couldn't, Bladon had good size and could fight. Later in the 70s, Schultz was moved out, they added some other guys, Holmgren and McIlharghy who could play, Harv Bennett and Hoyda not so much.
Two marquee franchises built of size and toughness, great to watch head to head. The rivalry between the two has picked up with the 0-3 comeback by the Flyers and then the bruins sweep the next year. The current Bruins are much more like the 70s version than the Flyers are. It's not a development I'm happy about.