Ok I would NOT use double sided tape or screws. If you use POP RIVETS by themselves then the fit will turn out great as long as you use ENOUGH rivets. In my case I used 25 rivets PER side and there were just 15 of those that were predrilled per each rocker. I used the EOS ZL1 style carbon fiber rocker panel skirts I have a rivet ROUGHLY every 4-5 inches. The rockers are ABOUT 7 feet long.
The RIVETS DO NOT show and since you are going through the stock plastic rocker panels then there is NO chance of rust if you use aluminum rivets. I installed the rivets with an AIR GUN for more clamping force.
As a side note, there was a 1LE at AMP that had his rockers just held on by tape also. VERY FLIMSY. SO basically there are alot of dealers NOT installing them correctly. It takes 2-3 hours to do the job right so I am sure that factors into their decision to SHORTCUT the process. Rather than putting the car UP on a lift it is BETTER to simply put the car on 4 jack stands so that the ARMS of the lift dont block your access. I cant see a dealer doing this EITHER. If neccessary, to REMOVE an installed rivet, simply drill out the center of it with a 3/16th drill bit.
Look at POST 66 in the following thread below:
https://www.camaro6.com/forums/showt...=602092&page=5