I would definitely do this on a flat surface before mounting, and be real careful if you use a skilsaw, it's really easy to bind cutting openings like that and get a kickback.
I wouldn't recommend it unless you are super familiar w/ skils.
The router may work depending on bit, and may be able to drill a start hole.
A jig saw is the safest, just tough to make super straight lines, maybe a new sharp blade and a guide/straight edge.
120G mixed reef, 17G planted
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.