Dave take a close look at Thin Film Resistor Networks. These are used in various precision electronic gear where extreme precision is needed. This one is from a Keithley DMM7510 7.5 Digit Multimeter and is stamped Fluke, I didn’t now that both companies were owned by Danaher. You may have seen a similar resistor trimming design on a large scale if you have ever purchased a high current monitor shunt except they use a hack saw to cut through the metal strap before painting to dial it into spec.