@doug_b_928 and
@Jett - just hold the mechanism in the same orientation that it is in the car so that the belt will release. Pull it ALL the way out and then grab the axle and push the belt back out thru the slot in the axle.
There is a pin that keeps the belt from pulling it back through - it slides out of the pocket in the belt and then (and this is important) WHILE STILL HOLDING THE AXLE AND PREVENTING IT FROM SPINNING, pull the belt back out of the slot.
At this point, I used a small screw driver slipped thru the slot to keep the axle from spinning out. When you're ready, you can then grab the axle, remove the screwdriver and then start spinning the axle against the tension until it stop. Then back off half a turn or so and reinsert the belt and install the pin, pulling the belt tight back into the slot.
Just be careful to not let the axle go as it'll spin out and release all tension. It's not a big deal and you can just spin it back again and all is well.
While I had the the belt off, I removed all the hardware I could and washed the belt in some warm soapy water before hanging to dry and then reinstalling....just make sure you get the hardware on in the right orientation and order.