I have proven that a fluid spacetime or vacuum or aether produces orbital precession assuming the model r = alpha / (1 + epsilon cos (x theta)) valid for small precessions. The precession is produced by well defined values of the spin connection components due to the fluid spacetime, vacuum or aether. I have also rechecked that the theory of note 362(5) is correct. Note 363(1) will report this new precessional proof, and will be built directly on Note 362(5). So this is another fundamental vacuum effect (similar to the g factor of the electron, Lamb shift, Casimir effect and energy from spacetime), the vacuum is responsible for orbital precession to any degree of precision, because in the model, precise experimental data from many experiments are used for x. Having found the spin connection components from the experimentally observed planetary precession, they can be used to predict tiny but real effects on the radial centrifugal acceleration of the orbit. They may also produce new accelerations in e sub theta. In the usual orbital theory these vanish for al planar orbits as shown in previous UFT papers. The use of elliptical polar coordinates may also produce precession. I also plan to investigate that in UFT363. One of the most elegant results of ECE2 to date is the proof just summed up in chapter 4 of the new book (just posted by Dave Burleigh in the publications section) that the most general theory of orbital precession is simultaneous solution of the ECE2 hamiltonian and lagrangian. So precession is intrinsic to the hamiltonian and lagrangian on the most fundamental level, and is due to ECE2 invariance (Lorentz invariance in a space with finite torsion and curvature). The same theory can be used for the Sommerfeld atom.