Nice analysis and write-up Duane! If you hear of anyone with any of the microcode disks or ALDs, let me know. Had saved an entire set but chucked them when I shut down my company (manufactured memory for 308X, 3090, 9121). Like below is my 3033/3036/3037 3D model on youtube for reference. Still need to work on the 3277s and have not had a chance to put the grill slots on the back panels of the 3036 doors and operator panel (new blender user so forgive me). You can see the B-console (left) is configured as the operator station with the VM/370 login screen and the A-console has the 3033 OP (operator) frame used to specify the IPL device and load the OS. Still have the layouts of all of the 3033 maintenance console screens so it would be fun to recreate the machine. IBM 3033 Processor Complex - Youtube