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Methoxy is a radical ubiquitous in the reactions of combustion and oxidation of hydrocarbon compounds in the atmosphere. Because of its relatively small size and degenerate $X~$$2$E ground electronic state, it presents a benchmark system for theoreticians to study the multimode Jahn-Teller (JT) effect in the presence of spin-orbit interaction. We have coupled an effective Hamiltonian, including Jahn-Teller coupling terms of up to 3 order, with a powerful computational engine that allows for quick calculations of spin-vibronic eigenstates and, correspondingly, eigenfunctions from which spectrum intensities can be derived. A graphical user interface, coupled with this computational core, helps to visualize the simulated spectra and compare them with the experimental traces. We simulate and discuss the intensities and spin-vibronic level positions, that we have observed in 4 dispersed fluorescence spectra obtained by pumping the $A~$ state vibrational levels 3$5$, 3$^1$4$^1$,3$^3$5$^1$ and 3$^3$6$^1$, and complementary data that have been obtained in SEP experiments of Temps and coworkers}.