Had a further look at this.
It is possible to pull in the sensor height and width from the Camera object - using Camer.CameraYsize and Camera.CameraXsize. This gives the number of pixels in X and Y, so (assuming square pixels) the sensor size ratio can be calculated., which means the height of the frame can be calculated from a set width.
Something like this, which I added:

                var scale = (Camera.PixelSizeX / Telescope.FocalLength) * 0.206;
                FOV = Util.FormatVar(Camera.CameraXSize * (scale / 3600.0), "0.000");
        FOV2 = Util.FormatVar(FOV * 60, "0.000");
                var ratio = (Camera.CameraYsize / Camera.CameraXsize);
        var height = Util.FormatVar(ratio,"0.00");
        var Yax = Util.FormatVar(height * 700, "0");
        var Yax2 = Yax+"px";
        camStat = "has " + (FOV2) + " arc min field of view - and a Y/X ratio of: " +height + " ,which is " + Yax2 + " display height (to the nearest pixel)"
There's some print to the screen of the calcs in that code, which I added just for testing.

The main problem is how to then send the calculated value to the DIV style attribute. Sure that can be done...just not certain how.