Some of the most tedious and boring work on an RV is rib prep. First you have to edge finish in all the little nooks and crannys. Then,deburr the holes, dimple, scuff, etc.
Here are half of them (the left half) complete. I’m about 1 hour in here.

For some reason I went faster on the second set. Here’s all 10. ready for cleaning and priming.

1.5 hours