Quaternion Rotations CanvasUI

I am trying to do an accelerometer and I got all figured out but I can't rotate my marker on the rectTransform Z axis and maintain X=0 and Y=0

the closest I could get was :
AngletoRotate is a value between 0 - 230
rectTransform.rotation = Quaternion.Euler(0, 0, AngletoRotate);
this one works perfectly but when I move my camera it also moves the marker...

I recorded a video of what I want and the problem I am having:
At the beginning of the video, you will see it working properly but when I decide to rotate the camera it breaks.

I don't know how to fix it ...Pls help =(

 

AngletoRotate = 180 / 230 * speed;

180 - how many degrees in the speedometer
230 - max speed

 

its 0 to 230 I have the math done already for getting the value. the problem is making unity do the rotation.
I know the angle rotation in Z i want is
float AngletoRotate = 230 - ((percentageMagnitude) * (MaxTreshhold - MinTreshHold) * -1);
but caling is not the correct way to go .
rectTransform.rotation = Quaternion.Euler(0, 0, AngletoRotate);

I want to hard set the rotation to the values (0,0,AngletoRotate) but I don't know how to do this

 

I think I found the solution. It was
rectTransform.rotation = Quaternion.Euler(rectTransform.eulerAngles.x, rectTransform.eulerAngles.y, AngletoRotate);
instead of :
rectTransform.rotation = Quaternion.Euler(0, 0, AngletoRotate);
wwhat a nightmare... well thansk anyway zxc76_die