I love adding bits and bobs to my panels... [smiley=thumbsup.gif]...!
My way: I paste the "panel.bmp" into Paintshop Pro 4 (=Free), then scroll my mouse around to the spot where I want to add the Gauge, at the same time observing the X-Y co-ordinates at the bottom of the PSP window.
When in the desired location, I make a note of the X-Y co-ordinates which I then enter into the next gauge line in the Panel.cfg notepad, and adjusting the gauge size...(and save it!).
With the Aircraft Cockpit loaded on the screen, I just toggle in and out of the Sim to observe the effect, and modify the panel.cfg file as necessary....re-loading the plane following any change to the details.
It works a treat...for me!...

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Paul...G-BPLF...FS 2004...always drilling holes in my panels..

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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.