Elod, here's a link to a petit RC's theard, a french forum, about a guy who made a 1/10 track on his garden, may help you. If you need translation, just aks
http://www.petitrc.com/_forumphp/showthread.php?t=44417
I'm also thinking about bfast diff, but no money for now... I need tires too, so, I'll make an order to TCModels soon, and try the hex alu mount, motor plate mount and this new alu gear, with some flip out jconcept tires
Bfast diff will wait... but I'm thinking about take 2.
Battle-axe : I saw cheap carbon fiber on ebay, check there.