Possible Z axis adjustment / improvement?

Specifications for the CNC suggest that the maximum working area is

• Max.workpiece dimension：200mm*300mm＜65mm

Z axis dimensions are <65mm

Measuring the total Z axis travel, there’s only 56mm of travel available….

it does look like I can slacken off the screws on the spindle a little to move it upwards to gain some workspace back,

great for using a sacrifical piece of wood orsomething on th ebase and maintain the full movement