diff --git a/Makefile b/Makefile
index 45a8b71..0761aa2 100644
--- a/Makefile
+++ b/Makefile
@@ -30,12 +30,14 @@ asm:
 	$(CADIUS) ADDFILE "${BUILDDISK}".po "/MILLION/" "res/PREFS" >>build/log
 	$(CADIUS) ADDFILE "${BUILDDISK}".po "/MILLION/" "build/MILLION.SYSTEM" >>build/log
 	for f in res/levels/*; do $(CADIUS) ADDFILE "${BUILDDISK}".po "/MILLION/" "$$f" >>build/log; done
+	bin/po2do.py build/ build/
+	rm "$(BUILDDISK)".po
 
 clean:
 	rm -rf build/
 
 mount:
-	open "$(BUILDDISK)".po
+	open "$(BUILDDISK)".dsk
 
 all: clean asm mount
 
diff --git a/README.md b/README.md
index 0c3417e..24411cf 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,5 @@
-# million-perfect-letters
\ No newline at end of file
+# Million Perfect Letters
+a shifty word game for the Apple II
+
+[Download latest Million Perfect Letters disk image](https://github.com/a2-4am/million-perfect-letters/releases/download/v1.0/Million.Perfect.Letters.v1.0.dsk)
+(version **1.0**, released **2022-01-18**, runs on any 64K Apple II)
diff --git a/bin/po2do.py b/bin/po2do.py
new file mode 100755
index 0000000..3e06b19
--- /dev/null
+++ b/bin/po2do.py
@@ -0,0 +1,33 @@
+#!/usr/bin/env python3
+
+import sys
+import glob
+import os.path
+
+kMap = {0x00: 0x00,
+        0x07: 0x08,
+        0x0E: 0x01,
+        0x06: 0x09,
+        0x0D: 0x02,
+        0x05: 0x0A,
+        0x0C: 0x03,
+        0x04: 0x0B,
+        0x0B: 0x04,
+        0x03: 0x0C,
+        0x0A: 0x05,
+        0x02: 0x0D,
+        0x09: 0x06,
+        0x01: 0x0E,
+        0x08: 0x07,
+        0x0F: 0x0F}
+
+indir, outdir = sys.argv[1:3]
+
+for infile in glob.glob(os.path.join(indir, "*.po")):
+    outfile = os.path.join(outdir, os.path.splitext(os.path.basename(infile))[0] + ".dsk")
+    with open(infile, 'rb') as f, open(outfile, 'wb') as g:
+        for track in range(0, 0x23):
+            sectors = [bytes(256)] * 0x10
+            for dos_sector in range(0, 0x10):
+                sectors[kMap[dos_sector]] = f.read(256)
+            g.write(b"".join(sectors))