Thanks for the pictures, that made it really clear. I think it may be more work than is even worth it though. I was thinking about building up a race B44, which is why I was asking about the saddle pack. I may just end up going with a Max Amps saddle pack. They have a 6000mah pack so that should give enough power/juice for such a light buggy. It is also already wired and all so I have everything I need to charge and balance it at home... here it is:
http://www.maxamps.com/Lipo-6000-74-Saddle.htm