I only vaguely remember doing this and I don't have a 395 to look at but if its in the case its pretty simple pull the parts off till you get to it remover it and put the new one in. Not much help but its hard to explain something so simple without overcomplicating it.
Not trying to be an azz here, but have you even tried before asking? It's any easy task.
You take the side plate off and remove the broke screw. There is a small rubber retainer that holds the screw in place, but you can either thread the screw through it, on just yank it out. (with a good pull) To reinstall the new parts, leaving the rubber retainer in place, screw in the new screw through the retainer, and put the adjuster in place and thread that on at the same time. You can either keep threading the screw in until it seats, or give it a good "shove" to seat it.