A little change is required in the script, please help.

I am using a script named as <Zoom to Width> that I found on web. This script does two jobs

(1) zoom to a specific percentage

(2) and center the page horizontally as well vertically at that zoom level.

I have changed the zoom value to 170% in it. Now the problem is that when script center the page at 170% it shows the middle of the page (horizontal as well as vertical). I need horizontal center but not vertical center of page, so I have to move to the top of page by scrolling or by moving cursor. I want a little change in it that vertically top of the page should appear instead of the middle of page i.e.

I want 170% zoom + horizontal page center + vertical page top.

I would appreciate any help. I am on Windows 64bit. Here is the script

//DESCRIPTION: Zooms to the width of currently selected object or the current page. http://www.in-tools.com

ZoomToWidth();

function ZoomToWidth(){

    var kAppVersion=parseFloat(app.version);

    try{

        if(File.fs == "Macintosh"){var isMac = true}

        else{var isMac = false}

        if(kAppVersion>=6 && app.generalPreferences.useApplicationFrame){

            var usesApplicationFrame = true;

            }

        else{var usesApplicationFrame = false}

        var sel=app.selection[0];

        var window = app.activeWindow;

        if(! (window instanceof LayoutWindow) ){return}

        var doc = app.documents[0];

        var horizViewPrefs = doc.viewPreferences.horizontalMeasurementUnits;

        doc.viewPreferences.horizontalMeasurementUnits = MeasurementUnits.points;

        var theWidth = doc.documentPreferences.pageWidth;

        var theHeight = doc.documentPreferences.pageHeight;

        var theSpread = window.activeSpread;

        var pagesLength = theSpread.pages.length;

        if(isMac){

            var windowWidth = window.bounds[3]-window.bounds[1]-35;

            if(usesApplicationFrame){

                window.zoom(ZoomOptions.fitSpread);

                var spreadZoom = window.zoomPercentage;

                windowWidth = (spreadZoom/170)*(theWidth*pagesLength);

                }

            }

        else{

            var windowWidth = window.bounds[3]-window.bounds[1]-50;

            if(usesApplicationFrame){//|| pagesLength>1 || theWidth>theHeight

                window.zoom(ZoomOptions.fitSpread);

                var spreadZoom = window.zoomPercentage;

                windowWidth = (spreadZoom/170)*(theWidth*pagesLength);

                }

            }

        if(sel && (sel.hasOwnProperty("parentTextFrames") || sel.hasOwnProperty("visibleBounds")) ){

            if(sel.hasOwnProperty("parentTextFrames")){

                var textFrame = sel.parentTextFrames[0];

                var frameBounds = textFrame.visibleBounds;

                app.select(sel.parentTextFrames[0]);

                }

            else{frameBounds = sel.visibleBounds}

            theWidth = frameBounds[3]-frameBounds[1];

            }

        else{window.zoom(ZoomOptions.fitPage)}

        window.zoomPercentage = (windowWidth/theWidth)*170;

        doc.viewPreferences.horizontalMeasurementUnits = horizViewPrefs;

        app.select(sel);

        }

    catch(e){}

    }