Is there a way for you to preset like some padding? I wouldn't really know. Unity is way over my head.
that's what i tried to do with the code snippet i pasted a few pages back. still unsure why that didn't work, it should be dividing fine.
It's been awhile since I've messed with Unity. I never liked UnityGUI and I actually at some point started using NGUI:
http://www.tasharen.com/?page_id=140 (you can get the source somewhere and get around the watermark I'm pretty sure, as long as you don't use it commercially).
Have you tried GUI.BeginGroup(Rect(whatever location and size you want)). This will make any following controls be positioned relative to the rectangle you specify in BeginGroup. So if you gave it a box at (100, 90) and then place a button at (0, 0), it would set it to (100, 90).
There are also some nifty methods in the GUILayout helper that might be helpful. Here is an overview on UnityGUI layout stuff:
http://docs.unity3d.com/Documentation/Components/gui-Layout.html