CAT SX Newcommer - Please Help!

[inferno_4wd]

Hi Guys, (I appologise in advance for these very basic questions but i'm a bit lost and would really appreciate some help!)

I have recently purchaced a CAT SX (Lipo edition) off of eBay to upgrade from my much loved CAT 2000EC, however all that i have is the Chassis + Body, i have no manual, box or spares. I was wondering what "In box" spares or parts i might be missing so that i can get them ordered.

I know the internal gear ratio can be adjusted, but again are the additional gears required normally supplied in the box? I have downloaded the manual from the website but i can see anything that really explains, just the ratio chart, but which is low, medium and high? Also which gears or pulleys are the ones that need changing?

Also to start i'm going to be running an Orion Experiance 2 motor/ESC (4000Kv) in it and i'm wondering what internal gear ratio and pinion/spur combo i should start with, i don't want to over stress the motor. I'm mostly running on grass, if this makes a difference and I'm assuming the chassis I have got is standard, but i won't know until i take a closer look.

Anyway, as i said before any advice would really be appreciated and if i haven't given the right (or enough) info please ask, i can also provide photo's if this will help.

Nick.