I'm gonna assume they're black pipe like mine. I simply wire brush the rusty spots by hand then paint them black. Nothing special.
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2000 Cherokee 29BH with 6V batteries, LED lights & 400 watts of solar power, flipped axles and raised. 2007 Tundra 5.7L DC-LB with lots of mods. C-co, 8/158th AVN Maint.