Replacing a part of animated mesh with bone weights I am trying to replace a humanoid part for my archer model. The full model is fully rigged and animated. It also has parts, which I am not replacing (clothes, archer bow, arrows, etc.). I merged meshes into a single object, where old and new meshes can be selected with CTRL+L shortcut. The full object looks like in the figure bellow.


However, the new model has no assigned vertex groups and the old model has. The weight paint mode looks like here
 

I am looking how it would be possible to assign weights from bones only on a new humanoid part and leave bow, arrows and clothes with their original weights. If I use "Weights > Assign Automatic From Bones" I am getting them assigned correctly to the new humanoid model, but it also assigns new weights for all other parts of the object (bow, arrows and clothes)


I was interested if there is a way to go around this, that only a part, which I am trying to replace, could get assigned automatic bone weights?
One solution would be to use vertex selection masking (in red circle on the image below) and select only new mesh vertices, then assign automatic from bones.
Second way would be to take new mesh out, place in the right spot in object mode and parent it to armature with automatic weights and delete old character body leaving cloths and weapon.