[longhorn70gmc]

Have you gotten the measurements for them yet off of your truck or another truck; have you checked the installation directions in the kit? Also, take a bolt and offset washer out and study it. You most likely already have a drill bit the same diameter of the bolt and that would be the first hole to drill. You may have to purchase a bit wide enough to drill the washer hole. This hole will be the depth of the washer. It fits in the hole level sunk with the wood when installed.
Remember....... When drilling these holes ensure you measure and clarify where the bolt hole in the metal/bed framing under the bed wood is so you get it right before you drill.
My truck is a longhorn, so my measurements may be different from yours. Another possibility you may choose is give MAR-K a call for the measurements on the type of bed wood/bed you are working with. GMC PAULS website may have measurements for holes as well. One more, I think there are some bed wood measurements on here somewhere that may help, someone please chime in to help this gentleman out? Good Luck on your bed wood install. I would start from the outside and work my way in from both sides. I enjoyed mine.
R/
Billy