We recently redid our kitchen and kept the existing double oven (24 inch)--only 5 years old. We did however, install a 27 inch cabinet incase we ever decided to replace this oven. Well the ovens computer board keeps failing so we have decided to go ahead and replace it. And, my cabinet guy is way too busy to deal with this.

Now I need to cut the opening bigger for the new oven. I am wondering what the best way to handle this is without making a mess of the white painted maple frame. I am wondering what the best type of saw to use to do a clean straight cut. I have to cut about an 1" on either side and 3/16 of an inch on the top.
Thanks Emerson Cooke