Working for my Dad, who ran a Printed Circuit Board shop.

One of his customers was making full-length 8-bit 512K RAM boards. My job was to insert components (caps, resistors, and sockets for the RAM chips and supporting logic IC's), trim the leads, solder into place and test.

This was early 80's when wave solder and solder masking technologies were rapidly advancing, leading to the surface mount processes we see today. They were also among the first shops to produce multilayer boards in the area.

Unfortuantely, due to the high costs of compliance with EPA regulations and disposal of the waste (primarily potassium cyanide IIRC) from the etching and plating processes, they decided to cease that portion of their business. I'd would have loved to seen firsthand how those technologies developed.