What's nice about a trim router, compared to the other wood router types like bulky plunge router or entire routing table, is that you can safely turn it on, hold it, and guide it with just one hand.

Using a tape measure and speed square, measure and cut the sides (A), ends (B), bottom (C), and lid (D) of the cable ...

The table rises a good few inches above the mounting base, but getting at the underside of the Router / Shaper is never easy. The proximity of the rotary tool makes things even more tricky, but ...

My idea to solve it is to trim a little surface 'A' using a router, but I am not sure from which direction to do it and with which type of router bit. Is this a good approach?

What's nice about a trim router, compared to the other wood router types like bulky plunge router or entire routing table, is that you can safely turn it on, hold it, and guide it with just one hand.