They say the max length is 40', but the longest reported Fifth Wheel is 42'. We have a 36' Class A and would have fit in a number of sites without issue. 42' will be sporty, but I believe doable. You may have to drop your Fifth Wheel to fit in the space, not sure. Many of the spaces are short and/or narrow and/or arced. So, review the satellite images before booking to see if you think you'll fit. That's what we did and everything was fine. For reference, we were in site 14 Gemini.

You would easily fit in one of the pull thrus. The back-ins would be iffy. If you look at an overhead on Google maps you can easily see which sites will and will not work for you.

Its been a few years and we did not park in that area, but I do recall seeing it and as I remember, yes you should fit but may need to unhook. Hopefully others will respond that have actual knowledge of the pull through sites.

You will need to call and talk to the rangers to be sure but I don't think that they are. I've only camped there once and that was years ago. The off-grid sites are very roomy (some of them.)

According to the website, the max vehicle length is 50 feet. You may have to use the parking area