Hehr window operator replacement questions

[63air]

I need to replace the Hehr window operators on one of the windows in my "63 Globtrotter as the gears are worn out but I can't figure out how to get the old ones out. There has to be some way to do it but I am just not seeing anything other than cutting the old arm. That then leaves the question of how do you get the new slider in the frame and hooked up to the new arm. I plan to get the new parts from VTS as they look to be almost an exact match to the old operators .This thing really has me stumped and I need some help.