Issue again! H&R Model 401 16 Gauge Pump Issues

my grandfather recently passed on a H&R Model 401 that could use some refinishing. I am camo painting the stock and pump which are both wooden then going over the metals with plain OD green so itll be simple to touch up scratches. The problem is i cant find any sort of diagrams on how to disassemble the shotgun. I dont wanna go pulling screws that i believe are correct and then pieces from the action go flying in all directions haha. Does anyone here have a similar shotgun? Model 400s and 402s are supposedly similar. Thank for the help guys!