That is correct.

You need one of these too, if the board isn't level your weights will be wrong.

http://www.amazon.com/Mayes-Level-10...4523032&sr=8-9

And you need a board or something else level. I used a Besta cabinet door from Ikea as a base. It is flat, laminated, fairly tough, portable, and I had it left over from my home theater project.

http://www.ikea.com/us/en/catalog/products/50116654

The subtrim in my transmitter doesn't effect the EPA.