TEC MA-1450: Rename TAX ie GST to HST, cancel a tax?

I have two taxes : PST and GST, now I just want one Tax : HST.
I was able to zero PST and GST, then reset the GST to new tax value. However, how can you rename GST to HST. I could not find it in the manual and also how to cancel PST so it does not print at all, right now it prints as zero tax.

I do have the S key.

There are suppose to be 4 taxes (TAX1/M...TAX4/M)
but where are they? I could not determine their location on the board and how to label them?

Can you also tell me how to re-name a department (also could not find it in the manual)
Thankyou.