SS-GCM: Bulk Sources, Junction Exchange and Smooth-Wall Controls for Scale Space Clock-Reading Geometry

We derive bulk null-energy constraints and a timelike-leaf junction benchmark for the corrected flat-clock times hyperbolic-four-space geometry used by SS-COS. A constant cosmological term cannot supply its source. For a specified reflection junction we compute the surface stress and its exchange with the bulk, distinguishing gluing choices from normal conventions. An asymptotic obstruction shows why a finite local wall cannot repair a retained product-geometry exterior within ordinary Einstein matter satisfying the null energy condition. We reconstruct a known smooth scalar wall as a comparator, derive its graviton and trial-photon normalization integrals, the transverse vector spectrum and a restricted coupling-floor obstruction, and extend it to a bounded finite-wall two-interface model with explicit boundary data and rigorous finite-window vector spectral bounds. The scalar wall is prior art, not a new Scale Space solution. A one-sided finite-extent action with signed Gibbons–Hawking–York terms and boundary potentials makes its local boundary-value problem explicit; this does not establish equivalence to the separate reflected-shell benchmark. These calculations delimit candidate parent geometries, boundary prescriptions and localization choices. They do not establish coupled perturbative stability, a physical doubled-shell gluing action or coupled second variation, dynamical closure for SS-DYN, or a cosmological flux law.