Helen for the rust on the running boards, just use a good iron dissolving wheel cleaner like Sonax Full Effect or 1Z Colourtec, it will neutralize and dissolve the rust and you can pressure wash it off. Its non corrosive and non-acidic.

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards