Bed Way 12"
You must drill and tap 9 holes in the new bed casting to match your lathe. You need three metric taps: M3x0.5, M6x1, and M8x1.25. If you don't have metric drills, you can use letter and number drills for tap drills. (The sizes are given in the bed extension instructions: see Chris' Tips tab for 1525.)
In your instruction manual, this part appears on the parts list as: