You will be surprised how much you can learn from you tube...a good service manual is priceless..plus lots of patients.
For tdc;
remove the fan on the passenger side of the motor and you will see a black plastic plug next to what is the pull start mechanism on a grizzly
remove the plug and look inside the hole, you will see the flywheel, there are three marks on it for tdc and advanced timing
when you set the cam in, make sure the bump on the cam faces straight up and there is a small spot on the side of the cam gear that shows through a hole in the valve cover to line up with the bottom tdc mark at the same time
Hope that helps