Both the Jaragars have screw-type case backs with glass windows. I used blu-tack to open them, a great tip I picked up on the watchuseek forum. This time, I avoided putting any on the glass windows, though to be honest I had previously opened both watches for regulation by just sticking a big ball of blu-tack on the back and twisting.
Here's the casual Jaragar opened up. When I bought these watches, I noticed the casual watch buttons had a much more precise and 'clicky' action compared to the dressier one, and here the reason is revealed. On the casual model, the quick set buttons extend right to the movement...
Whereas in the dressier Jaragar, the buttons push onto indentations in the plastic spacer bezel, which then presses on the movement. There is a lot of travel in the buttons before they change the day/date wheels. The photo below shows this different arrangement.
Time to take out the movements!