Well, the only displays that exist at the start of the game in the SP editor, when I can see my mode/ammo count, are #0 (Not sure about this one), #12 (the map), #26 (editor) and #46 (which we use to capture key events; not sure what it is really for and it doesn't have any controls). Definitely no #300 anywhere to be seen.
However, the idea doesn't sound too illogical, but using this little script I didn't find any of this sort of info being readable:
for "_i" from 0 to 10000 do
{
if (not isNull (findDisplay _i)) then
{
_display = findDisplay _i;
_controls = [];
for "_j" from 0 to 10000 do
{
if (not isNull (_display displayCtrl _j)) then
{
_controls = _controls + [_j, ctrlText (_display displayCtrl _j)];
};
};
player sideChat str [_i, _controls];
(str [_i, _controls]) createVehicle [0, 0, 0]; // Easier to read in the arma.rpt
};
};
Shame though...