Mike has some in the store they are hot bodies diffs. Don't get the pro cause it has a lower diff ratio.
http://www.rc-monster.com/proddetail...GY_DIFF&cat=47
These would be great to put them in.
http://www.rc-monster.com/proddetail...LM18700&cat=47
You can get these from mike as well. If you want to keep your bulkheads you have.
http://www.unlimitedengineering.com/...ore/13540.html
or a stronger one
http://www.unlimitedengineering.com/...re/13540B.html