you need lots of tenting.. 55degrees is the max possible assuming a standing desk, with table surface 2-3 inches below the elbow.
70 degrees is approximately the neutral point for the wrist, but obviously taking into account the thickness of the keyboard, you can't tent that high..
to approach 55degrees, you need 100mm m3 screws and 50mm m3 screws.. they're cheap on ebay..
THis works for the original ergodox,
If you've got an ergodox ez.. high tenting is a major problem, because it does not have a 90degree edge on the outer rim of the keyboard, it's rounded.
I suppose if you modify a rubber piece to fit under the rounded edge, it is possible, but well, then you might as well buy the original ergodox instead of doing so many mods.
Only the original ergodox can be tented to extreme angles..