Detecting browser print margins?

[Mango]

I'm trying to print some text in a very specific position on a page, so
that it will show through the window of an envelope when folded.

This is easy to do, as long as the browser's print margins are set to 0,
or I subtract the width of the margins from the position of the text.

My question is: is there a technique for detecting browser print
margins? It'd be nice not to have to warn users to set them to
something specific.

Cheers
Mango

 

[The Natural Philosopher]

I'm trying to print some text in a very specific position on a page, so
that it will show through the window of an envelope when folded.

This is easy to do, as long as the browser's print margins are set to 0,
or I subtract the width of the margins from the position of the text.

My question is: is there a technique for detecting browser print
margins? It'd be nice not to have to warn users to set them to
something specific.

Cheers
Mango

I am inclined to suggest, give up and offer a downloadable PDF..ther are
too many variables..paper size..Letter or A4..dpi settings.. browser
'interpretations'...