The triceps “thingy” I remember was something called a “cradle bench,” I believe. He built it. It was low off the floor, had a weird angle to it like a “V” and you put your elbows on the “V” portion and did some form of triceps extensions with your head down. I never used it but saw Makkaway do it.
The other triceps exercise I recall was a leaning foward rope pull. The weight stack was behind me, I was leaning forward in a lunge position with the ropes held in each hand over my head, and I extended my arms straight ahead.