Large C prints or Mural Prints were limited by the throat of the processor. 50 inch was the accepted largest size because the racks that transported the paper were supported on the two ends and would sag towards the center giving all sorts of problems.
As brought up earlier, the paper is in rolls, which hopefully is Roll Paper Dispenser, It is in a different room than the mural enlarger. At the last lab that I worked at in NYC, our enlarger was a 10x10 Fotar on tracks bolted into the floor. One would roll out a lot of paper, re roll it, put in a bag then a box many times, focus sheet, then a few test prints (strips) then the real sheet, loaded carefully into the processor. (thinking about it is going to give me nightmares tonight)
The digital prints are not projected as in the past. The technology has evolved many times. I had the service manual for a writer for a while. They have film writers and paper writers. As the drum spins a light pen almost touches and based on what color is to appear a combination of chemical compounds and varying current emit the wavelength desired. This happens many times until it is processed. That was early nineties. (I like the old days)
I had a twenty inch Colenta EP-2 processor( 12 min.) When RA-4 came out it was converted (4 min) RA Rapid Access.
My Ilford Cap 40s which was made for Cibachrome and processed many has been processing RA-4 (the 2 min per bath not a concern if the temperature is adjustable)