It would need some tricks / customized page layout to achieve your requirement.
Tricks:
1. set the map wider (not in ratio) to create space on both sides---say like set the map width from 450 to 750
2. use the following map title to create space at top/ bottom: (if neccessary)
</u><font size="100"> </font>
3. set map background opacity to 0%
(You will still find the map has limited space to put lines/ labels on this stage)
4. draw your lines partially first
5. prepare a background image to extend those lines
6. write addtional CSS style on your webpage to place the map and background image properly
Here is the example:
http://www.flash-presentation.com/prj/2 ... le/bg.html(But zoom / drag would realize the trick )
We can offer the service to setup it for the first time and prepare the background image.
You may let us know the detail if you are interested, we will estimate the possibility & cost.