If I recall, the way Tri X is notched, most cameras will rate it at 160ASA. It has always exposed well in my Canon 814XLS and Nizo 481. I tried using an external meter with TriX years ago and it was under exposed by more than a full stop. I find the amount of light loss from the S8 beam splitters to be a major wild card when trying to compensate. I would just spot meter with the camera and grey card.
It's a 1958 Bolex H16 so no light meter on board. I use a Gossen 6 as a spot meter. For some strange reason ambient metering was never taught to me back in the 80s, I guess by then all modern cameras had on board meters so hand-held metering was never taught? I taught myself how to spot meter on the Gossen anyway, it's pretty okay
What about those studio lights - can I find cooler modern replacements please?
