Quarter window roller replacement questions

So my rear quarter windows in my 71' Dart Swinger won't go down without a lot of effort and while trying to make them go down I can hear the rollers crumbling. What's the best/easiest way to replace the rollers?

Oh those are sooo much fun I can hardly describe it.:D
I pulled the entire assembly out of both sides and used nylon spacers from Ace to build new rollers.
A 4 inch grinder with a cutoff wheel and a mototool do the shaping by putting the nylon piece on a bolt with a nut to hold it while doing your shaping.
Now both windows work perfect.
I realize doing it this way is not for everyone, but a half a day and 12 bucks did the job.
It's been 5 years now without a problem one, and I roll them up and down a couple of times a week in the summer.

You may want to take a look for OE rollers.
Maybe something like this kit: Mopar 67 68 69 70 71 72 73 74 A-Body Quarter Window Hardware Kit Roller Clips | eBay

Interesting design those regulators, and it may be a good idea to take pictures.
One thing you don't want to do is mix up the parts side to side.:D