The crane available makes it a much simpler job. You'll have to grab the lower arm, and raise it up to the upper arm, and chain it off. I would disconnect the hoses right at the cylinder, and let the oil run. Then grab the upper arm, and lower it down to transport position. I would probably do the lower arm to get it off the ground for dragging onto the trailer, then do the upper arm after on the trailer.
You'll have to drag the house around with a chain, after releasing the swing hoses, and it may have a spring swing brake- That will take some book study to get it released to swing. A big wrecker and a low double drop would be what I would try to load it on.
So- lower arm chained to upper, remove the bucket if you have to, in order to get ground clearance. Swing the house to inline with the tracks. Release travel and roll it onto a double drop. Hook crane on the upper arm, and lower to transport. In order to get it off the trailer, you'll have to hold the upper arm off the trailer with the crane, while you roll it off with something else pulling on the house.
325 is a pretty big excavator, if I was trying to just load it all with cranes, I would use two cranes, one on the arm and one on the house, but you have to do all the work to get it in transport position anyways, so then you just as well roll it on the trailer instead of messing around and trying to pick it up and set it on a trailer.