diff --git a/src/fx/fx.hgr.48boxes.common.a b/src/fx/fx.hgr.48boxes.common.a
index ed1d9e8d1..0ee09e597 100644
--- a/src/fx/fx.hgr.48boxes.common.a
+++ b/src/fx/fx.hgr.48boxes.common.a
@@ -2,14 +2,19 @@
 ;(c) 2020 by 4am & qkumba
 ;
 
-src      = $00                       ; [word, must be at $00]
+src      = $00                       ; [word][must be at $00]
 dst      = $02                       ; [word]
 box      = $04                       ; [byte]
-stage    = $05                       ; [byte]
-any      = $06                       ; [byte]
-x        = $07
-rowcount = $07                       ; [byte]
+any      = $05                       ; [byte]
+rowcount = $06                       ; [byte]
+
+; order matters for the following group
+maskindex = $0A                      ; [byte][codegen]
+stage    = $0B                       ; [byte][codegen]
+m_dst    = $0C                       ; [word][codegen]
+o_dst    = $0E                       ; [word][codegen]
 BoxStages = $10                      ; [$30 bytes][must be at $10]
+
 hgrhi    = $40                       ; [$C0 bytes]
 hgrlo    = $300                      ; [$C0 bytes]
 
@@ -51,78 +56,82 @@ hgrlo    = $300                      ; [$C0 bytes]
          dex
          bne   -
 
-         ldx   #13
-         stx   x
---       ldx   x
-         ldy   #$7F
+---      ldx   #6
+         stx   maskindex
+--       ldy   #$7F
 -        lda   MIDDLE_STAGE, y
-         sta   ($0C), y
+         sta   (m_dst), y
          lda   OUTER_STAGE, y
-         sta   ($0E), y
+         sta   (o_dst), y
          dey
          bpl   -
 
+         ldx   maskindex
          lda   MiddleRowCounts, x
          ldy   #m_rowcount
-         sta   ($0C), y
+         sta   (m_dst), y
          lda   OuterRowCounts, x
          ldy   #o_rowcount
-         sta   ($0E), y
+         sta   (o_dst), y
 
          lda   MiddleFirstRows, x
          ldy   #m_firstrow
-         sta   ($0C), y
+         sta   (m_dst), y
          lda   OuterFirstRows, x
          ldy   #o_firstrow
-         sta   ($0E), y
+         sta   (o_dst), y
 
          lda   EdgeLeftMasks, x
          ldy   #m_edgeleftmask
-         sta   ($0C), y
+         sta   (m_dst), y
          ldy   #o_edgeleftmask
-         sta   ($0E), y
+         sta   (o_dst), y
 
          lda   EdgeRightMasks, x
          ldy   #m_edgerightmask
-         sta   ($0C), y
+         sta   (m_dst), y
          ldy   #o_edgerightmask
-         sta   ($0E), y
+         sta   (o_dst), y
 
          lda   LeftMasks, x
          ldy   #m_leftmask
-         sta   ($0C), y
+         sta   (m_dst), y
          ldy   #o_leftmask
-         sta   ($0E), y
+         sta   (o_dst), y
 
          lda   RightMasks, x
          ldy   #m_rightmask
-         sta   ($0C), y
+         sta   (m_dst), y
          ldy   #o_rightmask
-         sta   ($0E), y
+         sta   (o_dst), y
 
+         ldx   stage
          lda   CopyFlags, x
          bne   +
 
-         lda   #$A9
+         lda   #$A9                  ; LDA #$44 opcode
          ldy   #m_lda
-         sta   ($0C), y
+         sta   (m_dst), y
          ldy   #o_lda1
-         sta   ($0E), y
+         sta   (o_dst), y
 
-         lda   #$24
+         lda   #$24                  ; BIT $44 opcode
          ldx   #5
 -        ldy   MiddleBits, x
-         sta   ($0C), y
+         sta   (m_dst), y
          ldy   OuterBits, x
-         sta   ($0E), y
+         sta   (o_dst), y
          dex
          bpl   -
 
-+        dec   $0D
-         dec   $0F
-         dec   x
-         +LBPL --
-
++        dec   m_dst+1
+         dec   o_dst+1
+         dec   stage
+         bmi   +
+         dec   maskindex
+         +LBMI ---
+         jmp   --
++
          +BUILD_HGR_LOOKUP_TABLES hgrlo, hgrhi
 
 MainLoop lda   #0
@@ -403,16 +412,12 @@ copy0F=$9B00
 
 MiddleFirstRows
          !byte $0D,$0C,$0B,$0A,$09,$08,$07
-         !byte $0D,$0C,$0B,$0A,$09,$08,$07
 OuterFirstRows
          !byte $06,$05,$04,$03,$02,$01,$00
-         !byte $06,$05,$04,$03,$02,$01,$00
 MiddleRowCounts
          !byte $05,$07,$09,$0B,$0D,$0F,$11
-         !byte $05,$07,$09,$0B,$0D,$0F,$11
 OuterRowCounts
          !byte $13,$15,$17,$19,$1B,$1D,$1F
-         !byte $13,$15,$17,$19,$1B,$1D,$1F
 EdgeLeftMasks
          !byte %11000000
          !byte %11100000
@@ -421,13 +426,6 @@ EdgeLeftMasks
          !byte %11111100
          !byte %11111110
          !byte %11111111
-         !byte %11000000
-         !byte %11100000
-         !byte %11110000
-         !byte %11111000
-         !byte %11111100
-         !byte %11111110
-         !byte %11111111
 EdgeRightMasks
          !byte %10000001
          !byte %10000011
@@ -436,13 +434,6 @@ EdgeRightMasks
          !byte %10011111
          !byte %10111111
          !byte %11111111
-         !byte %10000001
-         !byte %10000011
-         !byte %10000111
-         !byte %10001111
-         !byte %10011111
-         !byte %10111111
-         !byte %11111111
 LeftMasks
          !byte %11000000
          !byte %10100000
@@ -451,13 +442,6 @@ LeftMasks
          !byte %10000100
          !byte %10000010
          !byte %10000001
-         !byte %11000000
-         !byte %10100000
-         !byte %10010000
-         !byte %10001000
-         !byte %10000100
-         !byte %10000010
-         !byte %10000001
 RightMasks
          !byte %10000001
          !byte %10000010
@@ -466,13 +450,6 @@ RightMasks
          !byte %10010000
          !byte %10100000
          !byte %11000000
-         !byte %10000001
-         !byte %10000010
-         !byte %10000100
-         !byte %10001000
-         !byte %10010000
-         !byte %10100000
-         !byte %11000000
 CopyFlags
          !byte 0,0,0,0,0,0,0
          !byte 1,1,1,1,1,1,1
@@ -508,7 +485,10 @@ BoxesY   ; starting byte offset for each box
          !byte $00,$05,$0A,$0F,$14,$19,$1E,$23
          !byte $00,$05,$0A,$0F,$14,$19,$1E,$23
 
-CopyParams ; must be immediately before BoxInitialStages
+CopyParams
+         ; must be immediately before BoxInitialStages so they get
+         ; copied into the right places in zero page
+         !byte 13
          !word $8D00
          !word $9B00
 
diff --git a/src/macros.a b/src/macros.a
index 4a5727004..b76d93fa0 100755
--- a/src/macros.a
+++ b/src/macros.a
@@ -106,6 +106,12 @@
 +
 }
 
+!macro   LBMI .target {
+         bpl   +
+         jmp   .target
++
+}
+
 !macro   LBNE .target {
          beq   +
          jmp   .target