Not sure if this is possibly pulling the tail of a sleeping dog. Why not consider removing them now while you have all this access to them? It might take a bit of spraying with PB Blaster or other rust breaker and carefully remove them and check them.
Why now? It looks like you have as much access as you'll ever have. Something bad happens, you're in a major repair, add it to the list. Once you put everything together and later decide its shock time and something real nasty happens, it might get ugly.
Or don't kick that sleeping dog until you have to.
Patience with any rusted fastener is a pretty good idea.
2005 Dodge Ram 2500 5.9L 6 Speed
16" Michelins, Hi Spec Wheels, Max Brake, Carslile Actuator, Equal-i-zer, Dill TPMS. Campfire cook.