Ok the way I did was is:

On row Initialize I find the checkbox and add the attributes to it:

var check = e.Row.Items[14].FindControl("CheckSpecific") as CheckBox;
checkbox.Attributes.Add("onclick", "return CheckSpecific('" + recordId + "');");

The record id is from: 
var recordId = ((MyObject) e.Row.DataItem).RecordId;

In the javascript method, i looped thru all rows to find the row with the same ID then add the logic I needed:

function CheckSpecificTaxLot(rowId) {
 
    var grid = $find('<%= wdg.ClientID %>');
    var gridRows = grid.get_rows();
    var length = gridRows.get_length();
 
    for (var i = 0; i < length; i++) {
        row = gridRows.get_row(i);
        var id = row.get_cellByColumnKey("RecordId").get_value();
 
        if (id == rowId) {
            // logic here ...
            // ...

            return (..boolean ..) ? false : true;
        }
    }
 
    return false;
}

Is this is the way to do or maybe there is a more efficient way?

Thanks,