Here is a pic of a new way my x500 is helping out.
The clamp is pushing the 'bow' out of the 1x4 so I can screw it to the studs.
(the studs are the start of exterior insulation on the walk-out basement wall)
The 1x4 is treated. As for the crack between boards for mice, I may cover that with aluminum or leave it --- a mouse nest with hot bodied mice in it is better insulation than the R-11 I am putting in!