Mirroring Parts

So I succesfully remeshed the part I needed. Fortunately, the part can be mirrored twice to create the remaining 3 parts.

The problem I am having is that the part is not being placed where the old parts are. It seems to be on the same path line, just seems shifted.

As you can see in the picture, I have the part I remeshed (using Bsurfaces) over one of the exisiting parts (top right). When attempting to mirror the remeshed part, the 3 mirrored parts don’t quite line up. (Mirrored parts are highlighted in orange)



Anyone have thoughts on how to fix this?

As an aside, is there a way to disjoin these 4 parts as one? As a last resort, I could invidividually move the parts to the correct positions? However, I would like to use a modifier to ensure it lines up correctly.

Thanks,
Nick

The object mirrors around the origin of the object name you have set in the mirror modifier settings. Ensure its origin is in the location you want it to be to give you the result you want. Also ensure ot does not have any rotation applied to the object (apply any object rotation with Ctrl+A)

As an aside, is there a way to disjoin these 4 parts as one?
Apply the modifier and separate loose parts (select all vertices and press P)