[Python] Python - Shift Longitude Coordinates While Converting a .gfc to a Zarr

I have a .gfc file that I would like to convert to Zarr format. The conversion works, but the longitude coordinates go from 0° to 360°. I want them to go from -180° to 180°. I posted a method in the code below, but this way I lose all types of georeferencing.

Is there a better way to do it?

import argparse
import numpy as np
import pyshtools as pysh
from pyshtools import shio
import xarray
import zarr
from osgeo import osr
import rioxarray
import rasterio
from affine import Affine

clm: pysh.SHGravCoeffs = pysh.SHGravCoeffs.from_file(
"xxxx.gfc",
format="icgem"
)

ds = clm.expand().to_xarray()

# problematic part
new_lon = ((ds.lon + 180) % 360) - 180
new_lon.attrs = ds.lon.attrs
ds = ds.assign_coords(lon=new_lon)

# other tested ways:

# ds['lon'] = ((ds['lon'] + 180) % 360) - 180

# ds = ds.shift(lon=-180)


store = zarr.storage.LocalStore("out.zarr")
root = zarr.group(store=store, overwrite=True, zarr_format=2)

DsMes = ds[["potential"]]
DsQlt = ds[["total"]]
DsCnd = ds[["radial","theta","phi"]]

DsMes.to_zarr(store=store, group="measurements", mode='w', zarr_format=2)
DsQlt.to_zarr(store=store, group="quality", mode='a', zarr_format=2)
DsCnd.to_zarr(store=store, group="conditions", mode='a', zarr_format=2)


Before:

Driver: Zarr/Zarr
Files: out.zarr/measurements/potential/.zarray
Size is 165, 83
Origin = (-1.097560975609756,91.097560975609753)
Pixel Size = (2.195121951219512,-2.195121951219512)
Metadata:
actual_range={62427044.0291816369,62529437.6430128664}
comment=pyshtools grid
extend=True
grid=DH
kind=real
lmax=40
long_name=potential
nlat=83
nlon=165
sampling=2
title=gravitational potential
Corner Coordinates:
Upper Left ( -1.098, 91.098)
Lower Left ( -1.098, -91.098)
Upper Right ( 361.098, 91.098)
Lower Right ( 361.098, -91.098)
Center ( 180.0000000, -0.0000000)
Band 1 Block=165x83 Type=Float64, ColorInterp=Undefined
NoData Value=nan
Unit Type: $m^2 s^{-2}$


After:

Driver: Zarr/Zarr
Files: out.zarr/measurements/potential/.zarray
Size is 165, 83
Metadata:
actual_range={62427044.0291816369,62529437.6430128664}
comment=pyshtools grid
extend=True
grid=DH
kind=real
lmax=40
long_name=potential
nlat=83
nlon=165
sampling=2
title=gravitational potential
Corner Coordinates:
Upper Left ( 0.0, 0.0)
Lower Left ( 0.0, 83.0)
Upper Right ( 165.0, 0.0)
Lower Right ( 165.0, 83.0)
Center ( 82.5, 41.5)
Band 1 Block=165x83 Type=Float64, ColorInterp=Undefined
NoData Value=nan
Unit Type: $m^2 s^{-2}$

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