2.5 years ago I made a BL track as well. With a upper-shassie I molded myself in CF I was able to pack the 6s Lipo-weight in the center of the truck (i had to move the drive train slightly as well).
I still drive it from time to time. The problem is that the total lipo pack has to be less than 4" * 4", so the selection is limited. Motor was the Lehner 2230, ESC MGM-compro.
It's mighty fun, but requires some space...