Recapitulating, before the madness...
1) Venus VSOP87
Attachment:
VSOP87_venus.jpg [ 108.42 KiB | Viewed 2717 times ]
2) Venus SPICE default (+ "earth_fixed.tf")
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SPICE_default_venus.jpg [ 99.54 KiB | Viewed 2717 times ]
Bad grid orientation (W), degrees, and planetary surface.
3) Venus SPICE default (+ "earth_fixed.tf + "celestia_venus.tf")
Attachment:
SPICE_celestia_venus_tf.jpg [ 102.36 KiB | Viewed 2717 times ]
good degrees and planetary surface, bad grid orientation (W).
There is not way to get the (E) grid. BUT:
4) Uranus VSOP87
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VSOP87_uranus.jpg [ 74.91 KiB | Viewed 2717 times ]
5) Uranus SPICE default (+ "earth_fixed.tf")
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SPICE_default_uranus.jpg [ 83.84 KiB | Viewed 2717 times ]
good grid (E), bad surface and bad degrees
6) Uranus SPICE default (+ "earth_fixed.tf + "celestia_uranus.tf")
Attachment:
SPICE_celestia_uranus_tf.jpg [ 83.47 KiB | Viewed 2717 times ]
they matches in all. Nonetheless the "rotation matrix" of the two "celestia_xxx.tf" is the same! In this case the grid was (E) in VSOP87 and is remained (E) in both SPICE settings, while in Venus was (E) in VSOP87 and then is become (W) in both SPICE settings.