Trying to modify conversion parameters

Hi,

I don't know if this has already answered so I apologize in advance if I'm duplicating themes. I've just purchased a Kobo Mini and I need to set two different options set for files to work in a proper way:
* Margins: I need no left and right margins. I don't mean 0 value, but no options in general class (.calibre).
* Page control: I need to set widows and orphans to 0.

I need these options to work for ebook-convert (not GUI), and for any output and input format.

Thanks in advance.

Ciao

Terisa