Left Margin in Invoice PDF

[roblaus]

I am trying to move the invoicing address (which is in my case the left one) about 1cm to the right in order to use it with a standard window envelope.
For this I set the parameter (line 512 or so in pdf.php ) to $pdf->SetX(20); but unfortunately to no avail. While SetY() works as intended (moved the address further down) SetX() didn't do anything. I even changed the width parameter so that the total width is <= 210 but this didn't change anything either.

I am not a programmer and this file is extremely difficult to read so please excuse me if I am on the wrong track altogether.

I am using a newly installed 1425