I can't say how those particular motors will behave at 36V, but I'm using DM452 drivers with 36V switch mode supplies to drive 3NM NEMA 23 motors with no difficulty. My gantry is way heavier than yours, has a 2.2kW spindle riding on it but it will rapid at over 10m/min and acceleration is fine for me.

Your 48V supplies may well be adjustable, look for a small trimmer near the terminals, so you might be able to reduce he voltage to somewhere near 45V to give the driver a bit more headroom.