Once I was satisfied with the triming of the bracket I used my Vice Crip C-Clamps to position the Landing Light Support Brackets in place prior to drilling. Images 1 thru 3 show how I checked the brackets for proper alignment using a bubble level.
Landing Light Support Brackets Clamped in place - Checked with Bubble Level
Landing Light Support Brackets Clamped in place - Checked with Bubble Level
Landing Light Support Brackets Clamped in place - Checked with Bubble Level