The CR-20 Pro has solid bed mounts. If any X axis gantry alignment is needed, you can use the "nozzle to bed" distance to check.

With M2.5 hex, loosen the 2 button head screws on the back side/ right of the X/Z Bracket.

If the right side is too low and needs to go up, squeeze the bracket and rail together while tightening the button head screws.

If the right side is high and needs to be lowered, you will squeeze the bottom wheel against the X rail while tightening.

When properly adjusted, the nozzle will be the same distance from the bed from left to right.

In some cases, it is necessary to do this process on the left side (near extruder motor) but requires partial disassembly of the machine.