Does anyone own both the MX and the C300. I do and it appears that they are not compatible. Does anyone have any solutions seems that the camera is to tall to fit in the gimbal...

In youtube they show how to balance the c100 and c300 on ronin-m which is the same as the mx except for the cage which can be removed

You may have limited movement on tild axis, thats depends on the setup of your c300, the weight of the lens, ff motors, transmitters etc.

And you need the Vertical adjustment arm extension kit (sparepart no 5)

Why you don't check Canon C300 Manual in which you get very clear and pictorial representation about how to embed camera into 3-Axis Gimbal Stabilizer. If needed then you may also ask Canon Camera Experts for help as they will advise you and helps you in your task.

https://www.facebook.com/photo.p ... ;type=3&theater

We use a C300 in a Ronin Mx whit Matrice 600