REYAX RYP820U mPCIE (actually USB2) GPS/GLONASS/BeiDou module and PPS
Unlikely to be possible without custom hardware.

Pin 42 in the mini-PCIe connector is defined as "LED_WWAN#" -- it's an activity LED for cellular modems. It's unlikely to be connected to anything on your motherboard; even if it is hooked up, it's probably to an LED, not to any hardware that can be read by the CPU.