Does anyone know if an ammeter in line between a Victor and the PD board is legal? Please respond ASAP.

So yes, a low-impedance current sensor is legal. Make sure it can handle the number of amps you could be throwing at it. CIMs can briefly draw around 100 amps under stall.

Another possibility is a current clamp. It a loop that wraps around the insulated wire and measures the current without touching the filaments so it doesn’t alter the pathway to motor, but a low impedance ammeter would work, or CAN can tell u the output current of a jaguar