pawn Code:
// Under OnGameModeInIt
XYZ = TextDrawCreate(26,300," ");
TextDrawFont(XYZ,2);
TextDrawLetterSize(XYZ,0.3,1);
TextDrawBackgroundColor(XYZ,0x000000FF);
TextDrawSetOutline(XYZ,1);
TextDrawSetShadow(XYZ,1);
TextDrawColor(XYZ,0xFFFFFFFF);
TextDrawShowForPlayer(playerid,XYZ);
// Under OnPlayerUpdate Or Wherever You Are Using This.
new Float:X,Float:Y,Float:Z;
GetPlayerPos(playerid,X,Y,Z);
new string[245];
format(string,sizeof(string),"X: %f Y: %f Z: %f",X,Y,Z);
TextDrawSetString(XYZ,string);
TextDrawShowForPlayer(playerid,XYZ);
EDIT: Fixed.