I just replaced the screen door paddle latch on my Monaco built Beaver. It was a real pain to do and required a bit of refabrication. I had to slide the plexiglass panel open and remove the slide trim insert that is above the latch. There I found two screws going down into the latch. They were firmly rusted in place and the heads broke off when I tried to unscrew them. I had to drill them out. There are the obvious two small bolts and nuts compressing the striker on the door lip. With these attachments removed you can remove the latch (with much wiggling cussing and complaining about how it is installed). I had to drill new holes in the aluminum spacer that was used to fill the gap between the latch and the door since I had been forced to drill out the old screws. After the latch is installed in the door, I had to carefully measure and cut off the striker to correctly impact the plate on the motorhome side.
The simple replacement of this latch turned out to be an all day frustrating event. But, I did accomplish the objective and the new latch works very nicely.
What happened with your old latch? The spring in mine had rusted in two and fallen out. In order to replace the spring, you would have to remove the latch, so I chose to just replace the latch with a new one. Good luck with your replacement, I hope it goes easier than mine.