detent 29 springs out when the cartridge is in its final position the cartridge can lie flush against the panel despite the projection of the twist lugs 67 since the leading lug is disposed within the bore 112 when the cartridge has been so positioned the usual fastening screws 116 are introduced and are tightened against and in their standard lock mechanisms 19 and 21 thus holding the cartridge against the door panel and making a firm assembly the screws can be tightened substantially since adjacent the places they go through the cartridge the cartridge is positioned and stiffened by the upstanding spacers such as 61 63 and 66 the cartridge plates do not bind on but leave the slide and interior parts quite free to operate while the actuators 16 and 18 could be mounted at this point it is preferred to provide a decorative escutcheon 121 over the cartridge the escutcheon is a dished plate with flanges 122 therearound adapted to surround the cartridge to receive and hold the escutcheon in place the plate 41 has at its top a bent lug 123 which twins with the lug on the adjacent plate 42 to provide a locating device for a central hook in the top flange 122 the escutcheon is hung thereon since the escutcheon also supports the operator 18 for rotation care is taken as the escutcheon is initially hooked and swung into position to make the proper interengagement between the secondary spindle 34 and the operator 18 the escutcheon has a lower apertured boss 127 which slips over the projecting primary spindle 26 to hold the escutcheon in place there is provided a spring pressed catch lug 128 at the bottom of the cartridge the lug 128 is a.