When I got my boat a few months ago, the guy threw in a set of telescoping outriggers. There were no mounts on the boat. I ordered a couple of base mounts on the internet and now need to install them. They are basically the same thing as a flush mount rod holder with a similar (about 30 degree) angle. Any advice on drilling the hole to install it in the gunnel? The thoughts I have are: 1) how do you get the 30 angle correct? 2) The "tube" is 1 3/8" around.I am thinking ifI drill the hole about 1.5" the correct 30 degree angle won't be so critical. Ant thoughts or recommendations?