If the gauge you want is already in the gauges folder and in an a/c that you already have ,then copy the line of text from the main panel section of that a/c's panel.cfg and paste it to the list on the panel.cfg of the a/c you need to add it to......change the number to the next consecutive.......
Change the size and position on the panel by manipulating the four numbers after the gauge,for example....
gauge38=L_Cessna!Avionics Switch, 59,666,37,46 ......first two numbers are the screen coordinates and the second two are the size parameters.....
...this is at it's simplest and will work for most gauges....if you need more than that then ask in the panel section as suggested by GB1......commoner


"In theory, there is no difference between theory and practice. But, in practice, there is."