Chrome remote mirror cable replacement? 78 Cutlass

[WanaBa442]

Drivers side mirror cable is broken, joystick creates no joy when you move it.
Have a replacement unit with a good cable, but the chrome is better on the original unit.
Mirror head comes off the stand with one screw, and then you can see where the three cables go into the mirror head. Plan is to snitch the good cable off the donor, pull the door panel and thread it up thru to the mirror head and.................
How do the cables attach to the head? Do they have a rounded end that gets captured in the spring loaded slots?
Really tempted to push in, slide over and pop the cable loose and replace with other cable, but don't know how many little springs, clips, retainers will fall out when I do (if any) or is it just that easy?

 

[Ribbedroof]

Have you tried soaking the existing 3 cables with marvel or ATF? Sometimes they get a little corrosion and that prevents the inner wire from moving in the jacket. I have saved a few this way.

 

[WanaBa442]

The original cable is now a deluxe " 2 piece non-operational simulated adjustment unit" , a deluxe option that you only get when the cable is in two pieces inside the door. The inner joystick end, and the exterior dangling frayed and broken end.
As my old farmer neighbor used to say "She come from together, didn't she?"