Issue recoloring gradients - only first stop changes

Hi all,

helping someone here out with a script to remove opacity.

started as a simple script and is growing more complex each day...

I've tweaked it so it can deal with gradients.

but it is only effecting the first gradientStop.

I am sure it's just something simple I have missed but it's driving me bonkers...

Thanks in advance.

function RemoveOpacity(){  
    // to work on selected items only set to SEL  
    // to work on whole document set to ALL  
    var work_on = "SEL";  
    //---------------------------------------------------------  
    function changeColor(obj,op){
        if(obj == '[SpotColor]'){  
            obj.tint = obj.tint*op;  
        }else if(obj == '[CMYKColor]'){  
            obj.cyan = obj.cyan*op;  
            obj.magenta = obj.magenta*op;  
            obj.yellow = obj.yellow*op;  
            obj.black = obj.black*op;  
        }else if(obj == '[RGBColor]'){  
            obj.red = obj.red+(255-obj.red)*op;  
            obj.blue = obj.blue+(255-obj.blue)*op;  
            obj.green = obj.green+(255-obj.green)*op;  
        }
    }
    var doc = app.activeDocument;    
    if(work_on === 'SEL'){  
        var items = doc.selection;  
    }else if(work_on === 'ALL'){  
        var items = doc.pathItems;  
    }else{  
        alert('the "work_on" variable is not set correctly');  
        return;  
    }  
    for(var i = 0; i<items.length;i++){ 
        if(items.filled === true){
            if(items.fillColor == '[GradientColor]'){
                for(var j = 0; j<items.fillColor.gradient.gradientStops.length;j++){
                    changeColor(items.fillColor.gradient.gradientStops.color,(items.fillColor.gradient.gradientStops.opacity/100)*(items.opacity/100));
                    items.fillColor.gradient.gradientStops.opacity = 100;
                }
            }else{
                changeColor(items.fillColor,items.opacity/100); 
            }
        }
        if(items.stroked === true){
            if(items.strokeColor == '[GradientColor]'){
                for(var j = 0; j<items.strokeColor.gradient.gradientStops.length;j++){
                    changeColor(items.strokeColor.gradient.gradientStops.color,(items.strokeColor.gradient.gradientStops.opacity/100)*(items.opacity/100));
                    items.strokeColor.gradient.gradientStops.opacity = 100;
                }
            }else{
                changeColor(items.strokeColor,items.opacity/100); 
            }
        }
        items.opacity = 100;    
    }  
}  
RemoveOpacity();