The 8mm Acme Anti-Backlash Nut Block is a great choice for any project requiring lead screw linear motion.
Note that the lead screw hole is not the correct pitch. (TR8-1.5 instead of Tr8*8)
Anti-Backlash Nut Block (Autodesk Inventor) 1.0
Anti-Backlash Nut Block for Autodesk Inventor