Years ago I worked in factory maintenance in two different forge shops, one for 7 years in a plant producing mainly brass and aluminum forgings, and the other for 6 years that mostly did steel forming for farm equipment.
In both factories the temp surrounding the operators at both ends of furnaces that heated the metal was 130 degrees through the summer months and around 75 degrees through the winter months. The loading end of the furnace was a better position then the unloading end where the forge operator worked. The load end paid a one step up in the wage scale then most of the floor work stations, and the operator end paid another pay scale step up, which was nearly the highest paid position in the plant. Both positions were highly valued and had a waiting list of people ready to step into the position. For the operator end, they couldn't even have a fan pointed directly at them without effecting the temp of the heated slug, having AC at that point would have been foolish.

Any job position more then 10' away from the furnace was 20 degrees cooler, and every foot farther away reduced the temps even more. The part of the buildings where the forge furnaces were, were separated from the rest of the building. Those forge furnaces provided most of the heat to the rest of the plant, iIn the winter, you really wanted to be in the forge furnace section of the plant. Most people outside of the forge section wore heave sweatshirts and light jackets and gloves during the winter.

As for the UAW strike during this time frame? I suppose they figure it may be their last hope to have a strike unless they can get into the new plant.
The labor unions are no longer there to assist the working man, they are now there to collect money to support the political party of their leader's choice, and assist those that really don't want to work.