Yup Bob thats what i'm doing, widening front to back 2"s each way. Thats pretty much what I planned on doing so thats kinda what i was looking for, just to be sure i had the procedure in mind correct since i have never done it.

You also bring up a something else i was wondering when you say stay close across the top. Looking at it i'm thinking cutting 1" from the lip across the top, should i stay that close to the opening or leave myself a bit more room for any reason?

BG