Cool! While I never had the chance to work with Zenith Z-160 or a TRS-80 Model 1, I can relate! My first PC was an Olivetti M19 (1986), which featured, like the Zenith, an ISA slot backplane and CGA graphics. No hard drive but a couple of 5 1/2 inch drives. It was powered by 4.77Mhz 8088. [0] I never had more fun than with that tiny box. It was my first machine I used to connect in dial-up to BBSs too.