Part of the information problem is just in the way RV are built. Winnebago gets a stripped chassis from those folks and then over the year, they add the coach/RV parts to that chassis. And some of those parts change as they buy and use the stock they have.
So if the step folks change their design in July and you get an RV built in September, there is no way to predict whether you will have a step built old style or new!
Winnebago does one of the better jobs of getting lots of info together and giving us the big folder of info but not all things will be covered by those extra manuals, so we do have to search out exactly what WE have because it may be quite different than the guy next to us.
Think of all the options available on the last car you bought and look at the vast number of things an Rv adds to that? Kind of like buying a truck with a house built on top. If we buy a house and the water heater fails five years later, we look for info from the water heater folks, not the builder.
The old days of things like cars being the same are gone, so part of finding a good repair place for our RV is finding one that knows how to find the right info!
First step of DIY is knowing how to locate the answers for things we have never done before!
Are you aware of the info Winnebago posts online to help sort things like the parts? This parts catalog will often give the correct part of many of the things we need:
https://catalog3d.winnebagoind.com/menu/Parts.htm
Note: It looks like the 2020 year group is down for changes , so you may need to check later?