To take the skid out, all you need to do is, loosing the tensioners, remove the for bolts and thats pretty much it. Heres a tip for the skid.. Take a tie down strap, and compress the suspension all the way down then tighten the strap. It make taking the skid in an out alot easier.
There is only 2 gears and a chain, in the chain case. Its very simple. Nothing will fall out when you pull the cover off.