An answer for me, and I hope someone else: February 14, 2018 Transitioning from a Mac 7500 (1995) & OS 9.1 to an iMac (2018) & OS 10.13.3 with a LaserWriter Select 360 printer. From articles on the internet: I could not get a print server to work for me, but a USB to Parallel printer cable did work. 1. I took the LaserWriter Select 360 Postscript Printer Description file from the Printer Descriptions folder, in the Extensions folder of the System Folder of Mac OS 9.1 (as my son suggested) and dropped it into the Resources folder<Contents folder< PPDs folder<Printers folder<Library folder of the iMac (hard drive) system drive. (Someone on an Apple forum said this PPD file goes all the way back to System 7, and this is the file you need.) 2. Plugged in a 10 foot USB to Parallel printer cable by StarTech, and set the rotary dial on the back of the 360 printer to “1” in order to set all connectors to Post Script. 3. When I selected + to add a printer in the Printers and Scanners window, the iMac chose “Default,” and saw the LaserWriter Select 360 as “Prolific Technology Inc. IEEE-1284 Controller” under Name, and “USB” under Kind. Next, I selected that listing, “Prolific Technology Inc. IEEE-1284 Controller” and then moved to the Name rectangle and gave my printer the name “360”. 4. In the “Use” rectangle, I chose Select Software…, highlighted “Apple LaserWriter Select 360 v2013.112 in the Printer Software window that appeared, and clicked OK. Then I selected “Add.” The printer was added. 5. I chose “Options & Supplies,” chose “Options,” and then set Memory Configuration and Cassette to match my printer. Or if I chose “Configure” before the printer was added in step 4, I could set the memory and tray options there. 6. Otherwise, Tray options can be set when printing; under “Paper Feed” by choosing “Notes.” 7. Both the Mac 7500 and iMac are connected to the LaserWriter Select 360.