Well you have a job ahead of you sir. The upright needs to be removed along with the dash cowl and seat deck for easier access.
The brakes are inside the diff housing. If you are pulling the transmission, you can leave the axle ends with the brakes on until you get it on the floor or work table but I always took the axle ends out before pulling the transmission to reduce the weight and bulk.

You will need to find a manual for sure. I cant supply it but you should be able get a service/overhaul manual from your Local Clark dealer for a reasonable fee.

Good luck!