From your pictures my unit looks the same as yours. Can't tell if the parts are for a 540 or what, since the loader is actually a BushHog 2445QT, but the CV assembly appears to be the same.
My question is, I know there is 1 snap ring on each piston, just behind the larger 19mm nut, which I removed with an awl. Is the other snap ring in the same location or a different one? Are 2 nuts the ones in the pictures?
Since you replaced the whole Joystick Assembly, where do you disconnect it? Is the same removal procedure required to remove the whole joystick assembly?