I took the windows
out of my Ventura
a few days ago and have been cleaning them and have ordered the same part online from Vintage Campers because Vintage trailer supply was all out of the rt hand version.
I just went out and looked at the set up on our trailers and was able to get at the part without taking too much apart. I think you probably should be able to do it without taking out the window again.
On the side that the crank is on, there is a piece of gray plastic that runs the height of the window.
I removed that and took out all the screws on both sides of the bottom rod only.
I then took each side of the bottom rod off the crank bar that runs the height of the window.(pic 1)
I was able to move the left hand side up towards the top of the window (pic 2) and with some wiggling got it at enough of an angle that the crank mechanism on the right side came out of place and I was able to take it out and remove it from the rod. From there it would be a simple thing to put the new one onto the rod and reverse the process to get it into place and replace the screws.
I just noticed that one of the pictures is blurry, let me know if you want a better one.