After my window fell down, I did this DIY and glad I did, it probably saved me about $250 and cost less than 10$ to do the DIY.
Some more notes:
No matter what before you even start.. get the 2 new white sliders, they are like $2 each at the dealer.
The arms are supposed to pop in there tightly and don't come off easily, so don't reuse the originals!
Don't just straighten the arms, bend them in a way so that the ball should be at a 90 degree to the sliders, be careful not to rough up or damage the ball.
While you're in there, do the smart thing and spray a lot of anty-rust
Also, for sport models or those with an air bag:
The bluddy screw is behind the SRS little logo, remove the plastic piece and unscrew to get the the panel off.