Here is a sample file to prove Rsts V4A-12 will actually run. I didn't put all the utilities on it, I'll let you do that. Make sure you set simh for 11/20 or it won't run at all. I included the papertape reader, punch and TM0 tape drive. PDP-11 simulator Vx.x-x sim> set cpu 11/20 Disabling CR Disabling XQ sim> att rk0 RSTSV4A.DSK sim> boot rk0 RSTS V4A-12 RSTS.ORG OPTION?