How can i remove the sku column from Magento invoice PDF? and i tried to make some changes which those files but it's not working for me.
app/code/core/Mage/Sales/Model/Order/Pdf/Invoice.php to app/code/local/Mage/Sales/Model/Order/Pdf/Invoice.php
app/code/core/Mage/Sales/Model/Order/Pdf/Items/Invoice/Default.php to app/code/local/Mage/Sales/Model/Order/Pdf/Items/Invoice/Default.php
app/code/core/Mage/Sales/Model/Order/Pdf/Abstract.php to app/code/local/Mage/Sales/Model/Order/Pdf/Abstract.php