diff --git a/sfm/report_pdf.py b/sfm/report_pdf.py
index a793b08..794c836 100644
--- a/sfm/report_pdf.py
+++ b/sfm/report_pdf.py
@@ -856,9 +856,12 @@ def _draw_waveform_subplot(fig, gridspec_cell, rd: ReportData) -> None:
     order = ["MicL", "Long", "Vert", "Tran"]
     has_sc = bool(rd.sensor_check_waveforms)
     if has_sc:
-        # main lanes + a narrow sensor-check strip column on the right
-        inner = gridspec_cell.subgridspec(4, 2, width_ratios=[1.0, 0.15],
-                                          wspace=0.04, hspace=0.0)
+        # main lanes + a narrow sensor-check strip column, flush against the
+        # main panel (BW shares the border — no gap), with the "0.0" baseline
+        # labels moved to the right of the strip.  Proportions match BW's
+        # Event Report (main ~0.75 / strip ~0.10 of the panel width).
+        inner = gridspec_cell.subgridspec(4, 2, width_ratios=[1.0, 0.13],
+                                          wspace=0.0, hspace=0.0)
     else:
         inner = gridspec_cell.subgridspec(4, 1, hspace=0.0)
     sr = rd.sample_rate_sps or 1024
@@ -902,9 +905,12 @@ def _draw_waveform_subplot(fig, gridspec_cell, rd: ReportData) -> None:
         # Channel label on the LEFT (matches BW)
         ax.set_ylabel(ch, fontsize=8, rotation=0, ha="right", va="center",
                       color=_channel_axis_color(ch), weight="bold", labelpad=14)
-        # "0.0" on the RIGHT (BW convention)
-        ax.text(1.005, 0.5, "0.0", transform=ax.transAxes,
-                fontsize=7, color="#555", va="center", ha="left")
+        # "0.0" baseline label on the RIGHT (BW convention).  With the sensor-
+        # check strip attached, it goes to the right of the STRIP (drawn below);
+        # otherwise just outside the main lane.
+        if not has_sc:
+            ax.text(1.005, 0.5, "0.0", transform=ax.transAxes,
+                    fontsize=7, color="#555", va="center", ha="left")
 
         ax.grid(True, linestyle="--", linewidth=0.3, color="#bbb", alpha=0.6)
         # Vertical dashed trigger line at t=0
@@ -944,6 +950,9 @@ def _draw_waveform_subplot(fig, gridspec_cell, rd: ReportData) -> None:
             scx.set_xticks([]); scx.set_yticks([])
             for _s in scx.spines.values():
                 _s.set_linewidth(0.4); _s.set_color("#999")
+            # "0.0" baseline label to the RIGHT of the strip (BW convention)
+            scx.text(1.10, 0.5, "0.0", transform=scx.transAxes,
+                     fontsize=7, color="#555", va="center", ha="left")
 
     # Trigger triangle marker ▼ above the top channel at t=0
     top_ax = main_axes[0]  # MicL