How To Place Outlets In Fireplace Built-ins?

[EddieO]

I am getting ready to make my first built ins around a fireplace. I planned on making the carcasses about 1/2" less deep than the actual measurement so I know they will fit behind the mantle which wraps around 2 corners. The owner wants the 2 wall outlets and cable outlet to be installed on the back of the units. Two questions:
1. How do I find the exact spots for the outlets on the back of the units without screwing it up?
2. How can I put the outlets on the back if they're going to be 1/2" off the wall?

Eddie

[BobbtheEE]

There is probably and easier way, but what I have done years ago while installing wall paneling is:
1) temporarily remove the receptacles.
2) install a box extender.
3) tape carbon paper, carbon side out, over the box extender.
4) place panel into position, and tap on the location of the box with the palm of my hand.
This will leave an outline of the box on the back of the panel.

Note that this was before the invention of Rotozip tools which have guided bits that will follow the outline of a box from the front.
Bob