go under and over then do diamond plate covers. i have the plastic caps and i wish i had over the rail. I have the good caps and mine are starting to pull up at the corners only after a year and a half.
2004 EXC Silverado 6.2L
Mods:
6.2L L92, Ported and Polished stage 3 heads, 95mm Throttle Body, 100mm MAF, NA, Pacesetter LT Headers, Magnaflow X-Pipe Muffler, Electric Fans, 160* thermostat, 2" Drop Shackles, Hellwig Sway Bars Front and Rear, Monroe Reflex Shocks, NGK Spark Plugs, AMW Oil Catch Can, 17"x10" wheels on Kuhmo Tires.