Can I change the heading of Tax summary

How do I change the heading on the tax summary report to read GST summary and not tax summary. At the moment I put it in PDF then change it from there . would be nice if I dont have to do that extra step before printing

You cannot because it is hard-coded. The reason is that you might have tax codes selected that are not GST, depending on your jurisdiction and business practices. So if that change is important, modifying the PDF is the only approach.