I'd like to see some pics of this "ghetto mod".
Here are a couple of quick cell phone pictures to demonstrate the idea. If you spend more then thirty second on it's construction, it would turn out far nicer. A scrap of sheet steel bent in a [ shape for example.
First, this is the beginning fullsize keyboard centered in front of the monitor with mouse setup off to the left.

Here we have construction of the mod. A box of "checks"(I'm told they're like an electronic money transfer, but from the analog age) happens to be the same height as the keyboard.
*Lego used to conform to international GeekHack picture standards.Finally, we have the end result: a ghetto tenkeyless. Hakuna matata, baby! This particular mouse pad is a very thick rubber and spreads the force out evenly. Despite the left side being placed directly on top of the key caps, they do not actuate.

Play around with it, see how you like it, and
then spend $100 on a board.