Totalling Tax Breakup in Sales Invoice

Hi All,

Please refer the screenshot below to address the query.

At the time of printing the sales invoice, there is a section called tax breakup which displays the tax charged on the basis of HSN/Code. I would like to add a total row(bottom) and total column(right-most column), which sums up all figures and matches to Grand Total amount.
How to implement the same?

Thanks in advance,

The creation of this table is hard-coded as of now. To add total row and column, you have to overwrite the related method via a custom app.