Clear the mod signal, connect the PMA output to an add node afterwards, then use a peak node to display the actual PMA value that is being sent out:
8c1bb760-96a7-4b47-aaf5-fd6ce4e134ac-image.png
From then on, use the external display buffer to visualize it however you like (or you can send it into a global_cable node instead of the peak signal if you don't need a continuous visualization).