Letterhead Specs for Report Designer

SOLVED

Hi Everyone!!

We just launched a new logo and I am trying to put it into our reports in Timberline.
In order to do it, I go into the report designer > options> letterhead and change the link.

HOWEVER, all of the logos that we tried either have a black background or a gray/yellow background in it. 
I am trying to get my hand on the specs that work best, but haven't been able to find it anywhere.

Can anyone help me?

We spent all this money on a new logo, so we want it to look crisp and clean on our reports for subs and bills for clients!

Thanks!

Cassy