You need to adjust the rotation of the steering wheel in the .plr file. Limit the degrees of rotation and you will find that you don't need to turn the arms off.A bunch of mods have driver hands—however since rFactor doesn't know anything about the hands, they're strictly bound to rotation of the wheel, which is not how it works in reality. So, if the arms are made at the natural angle, they pop up onto the middle of the screen at a high wheel angle—and the alternative is that in the neutral position the arms only stick out at the center bottom of the screen, as if they are attached at the driver's chest.
To sum it up, once you try it, you wish that all mods let you turn the arms off.
I have spent literally DAYS of my life, changing the angle of the arms, varying the pivots, adjusting rotation.... all to achieve a smoother, more realistic movement. It's not as good as AC, but it's an improvement.But then the wheel movement isn't realistic (can't have everything, lol). Though I agree, that disembodied arm popping onto the screen is quite distracting. There was a "3D Arm" mod, but i never tried it, having read it was problematic.