Dunno about your rig, but mine is aluminum framed with smooth fiberglass sides and it clearly shows off it's entire skeleton when covered with a morning's dew. It would be really easy to see and mark the best pots to anchor your rail if you catch it at the right time.
As for how I actually did mine, I chose my spot, measured and chalked a level line. Where my rail came with four screw holes, I opted to add an additional hole in between each original hole for a total of seven. I placed the rail where I wanted it on the level line and marked the holes. I drilled appropriate sized holes and installed the rail with stainless pan head screws with clear silicone sealer on the back of the rail and around the screws.
I couldn't place my rail close enough to the LP outlet to use the 3ft hose that came with the grill so I had to go get a 12ft hose and put the quick connects on it. That does give me the option to use the grill on a table up to 15ft away as well.
2011 F-250 Sooper Dooty 4x4 "Menthol"
2010 Sunset Creek 267 RL "Not Far"
(Not far sale, not far lease, not far rent, not far loan and not far from home)