i think this is what you are looking for. it allows you to use smaller servos without having to drill the chassis again
http://www.lefthander-rc.com/catalog/product_info.php?cPath=35&products_id=1044
Rusty NutZ
http://www.lefthander-rc.com/catalog/product_info.php?cPath=35&products_id=1044
Rusty NutZ