All done, thanks everyone!

"Bob" wrote in message
m...
Good Friday - I am running a dryer vent through as a outside wall in the
laundry room. Is there a trick to cutting the inside and outside 4 inch
holes so they line up? The studs are 2x6 inch. The outside wall
placement is an area that is hard to reach from a ladder, so I don't have
easy access for a lot of outside measuring. Thank you