@User I'm trying use the io_analog ports on top of the caravan harness and designing my esd as recommended, I'm just making sure I understand exactly what io_clamp_high and io_clamp_low are connecting to before I launch into it. I have some simple diode clamps borrowed from another project like as shown in blue below. Is the circuitry under io_analog 4-6 a power clamp as drawn in brown below? Or are they just clamps to one of the power rails on chip? What exactly is it connecting to? Thanks.

The circuitry is a power clamp like you show above. The clamp "high" needs to be connected to a power supply, and "low" to the ground return. Otherwise the circuit is just floating. It does not even have to be connected to the pad it's under, although that's the obvious connection because it has the shortest path for shunting current.

Excellent. Great news. Thank you!