Hello and welcome to JustAnswer!
To remove the pin from the differential from the C205f front axle you have to drive a roll pin out. This can't be done with the axle in the truck. You have to remove the ring gear from the carrier to get to the roll pin, the differential carrier has to be removed from the axle housing to remove the ring gear. As you have already seen, there is no room to get the carrier out because the frame is in the way, so you have to remove the entire differential assembly from the truck for any internal repair. Once its out you have to use a large spreader fixture that engages the two large holes on the front of the housing. This speader actaully spreads the axle housing apart to relieve the preload on the side bearings to be able to remove the carrier. These are set up just like a Dana for side bearing preload.
You're trying to replace the stub shaft that goes between the differential carrier and the cv shaft right? I'm guessing stripped splines between the stub shaft and the cv shaft?
The shafts just slide into the carrier and lock in with lock rings. There aren't any c clips like older axles if that's what you were wondering about. You'd just have to get the stub shaft off the cv shaft and slide it back in, or if its damaged or you can't get it off all you have to do is slide a new one in. Does this answer your question or am I out in left field?