I actually had the exact same issue except on the driver side. A little bit of coolant leaking after it was cold was when I really noticed it but it was actually leaking while running too. Anyway it was coming from the top of the radiator on the tank. It was where a little circle that’s from manufacturing, I’ll post a picture soon. It was under the piece of the fan shroud that mounts to the top of the rad. I found it by complete chance so it wouldn’t hurt to check for it in your situation. I took some JB water weld and patched it right up and i was good to go. Other things I would check for is the thermostat, mine was leaking from there as well, took the hoses and part of the thermostat where the hoses attach was rotted away.

From my expierence, check everywhere there is a plastic fitting and be very careful, if it wasn’t the broken piece, it probably will be if you hit the wrong way or tighten a clamp too much.

As for monitoring temperatures I do it with a $15 dollar ELM327 obd wifi plug in and a $10 app (OBD Fusion) on my iPhone, it’s a little buggy but for the price couldn’t beat it.