All measurements look good. Jillena pilot-drills for the lag bolts.

Jeff drives in a lag bolt with the pneumatic impact driver.

The window frame has been set and shimmed and is secured with the ratchet strap across the outside. Here, Jeff is pilot-drilling the screw locations in the frame.

Screwing the frame to the casing.

Once secured, the jamb liners got put back in, and the sashes hung. Our first twin window doesn't look to bad from the inside...

...or the outside.