The GUT group paper identified SO(10) as the grand unified group of the Cohesion UFTand established that MGUT is the density threshold DGUT at which all three recursionmode frequencies become equal. This paper derives MGUT numerically and calculatesthe resulting proton decay lifetime. The calculation uses the one-loop renormalisationgroup equations — identified in the running couplings paper as the density-dependenceof the recursion mode frequencies — with the Standard Model particle content below theelectroweak scale and the additional recursion modes required for exact unification aboveit. With additional recursion modes above the TeV scale, the three couplings convergeprecisely at MGUT ≈ 2 × 1016 GeV with αGUT ≈ 1/25, giving τp ∼ 6 × 1034 years forp → e+π0 — consistent with the Super-Kamiokande bound (τp > 1.6 × 1034 years) andwithin reach of Hyper-Kamiokande. An appendix records the researcher’s hypothesisthat, within the Cohesion UFT framework, the proton may have no physical decaymechanism.