diff --git a/src/ov_SC01_074/ov_SC01_074_jr_8017BE9C.c b/src/ov_SC01_074/ov_SC01_074_jr_8017BE9C.c
index 197b8fece4..673a6076dd 100644
--- a/src/ov_SC01_074/ov_SC01_074_jr_8017BE9C.c
+++ b/src/ov_SC01_074/ov_SC01_074_jr_8017BE9C.c
@@ -3488,7 +3488,56 @@ extern s32 func_8012AD50(void *a0);
 
 INCLUDE_ASM("asm/ov_SC01_074/nonmatchings/ov_SC01_074_jr_8017BE9C", func_8017E07C);
 
-INCLUDE_ASM("asm/ov_SC01_074/nonmatchings/ov_SC01_074_jr_8017BE9C", func_8017E158);
+#include "common.h"
+
+/* identical layout to SVECTOR_8016E7C8 (src/shared/engine_types.h);
+   own tag so this draft compiles standalone via match_one (no shared TU). */
+typedef struct { short vx, vy, vz, pad; } SVEC_8017E158;
+
+void func_8017E158(SVEC_8017E158 *p0, SVEC_8017E158 *p1) {
+    /* conform to the sibling TU's canon (`extern void func_8012EF70(s32, s32);`)
+       and read the GTE flag through a cast at the call. */
+    extern void func_8012EF70(s32 a0, s32 a1);
+    extern void func_8017E3E0(void *a0, void *a1, void *a2, void *a3);
+
+    SVEC_8017E158 prev;
+    SVEC_8017E158 cur;
+    SVEC_8017E158 lo0;
+    SVEC_8017E158 lo1;
+    SVEC_8017E158 sv0;
+    SVEC_8017E158 sv1;
+    SVEC_8017E158 sv2;
+    SVEC_8017E158 sv3;
+    s32 more;
+
+    more = 1;
+    cur = *p0;
+    do {
+        prev = cur;
+        cur.vz += 0x40;
+        cur.vy = p0->vy + (p1->vy - p0->vy) * (cur.vz - p0->vz) / (p1->vz - p0->vz);
+        if (cur.vz >= p1->vz) {
+            cur.vz = p1->vz;
+            more = 0;
+        }
+        lo0 = prev;
+        lo0.vy -= 4;
+        lo1 = cur;
+        lo1.vy -= 4;
+        if ((((s32 (*)(void *, void *))func_8012EF70)(&lo0, &sv0) & ~0x1000) == 0 &&
+            (((s32 (*)(void *, void *))func_8012EF70)(&lo1, &sv1) & ~0x1000) == 0) {
+            lo0 = prev;
+            lo0.vy += 4;
+            lo1 = cur;
+            lo1.vy += 4;
+            if ((((s32 (*)(void *, void *))func_8012EF70)(&lo0, &sv2) & ~0x1000) == 0 &&
+                (((s32 (*)(void *, void *))func_8012EF70)(&lo1, &sv3) & ~0x1000) == 0) {
+                func_8017E3E0(&sv0, &sv1, &sv2, &sv3);
+            }
+        }
+    } while (more);
+}
+