When I go into an old gun for the first time I photograph the action with all the parts in place. I take more photos as I disassemble the innards. This way I know how everything is supposed to hang together when it is reassembled. Remember the Golden Rule in gunsmithing: "IF IT DID NOT REQUIRE A HAMMER TO TAKE IT APART. IT SHOULD NOT REQUIRE A HAMMET TO REASSEMBLE IT.' There are, of course, exceptions to every rule. Very rare, but exceptions none the less.