I did. It's quite tricky. You will have to work out how high you want the TV to be. Rule of thumb is to have middle of the screen or 1/3rd of the top of the screen at eye-height.
Then, you will need to translate that into the height of the TV mount. So if you have a specific type of TV and TV mount, it's relatively easy to do. If you don't, you need to make some assumptions.
This height is going to be the middle of the noggin placement.
I've asked them to tilt the noggins so that 1) there is space behind them for cabling and 2) the surface area available for placing the TV mount is larger.
You could always add noggins at multiple heights if you're not exactly sure which height they need to be at. Note also the Home Theatre and Automation folder on the forum and this thread in particular: viewtopic.php?f=34&t=79039
Hope this helps!
That does sound tricky!! Thank you!
Did they charge you to add the noggins?