If it was me and I wanted to re-clear and better UV protection, I would get all the loose stuff up, pull the awning, rubber, etc, mask the vehicle, scuff, and shoot it with automotive clear. Its up high so it doesn't have to be perfect and will look 1000x better than rhino liner which is always a bodge. You have a natural split line plus a rubber gasket so it will still look great.
A mid-tier harbor freight gun and some duplicolor or same-tier clear coat would look good for quite a few years without a ton of prep. You could even do it in your driveway on a still day and you will be happy with the results. Lay it on decently heavy and that will help blend the edges if you dont get a perfect sanded blend. Again, its a roof up high on an old vehicle. You are not building a church.
Tough to tell from the pics - I would probably leave the bolts alone and cover them with some RV roof sealant when done. That way you can still pull the bolts later if needed.
