Even with the added seat boxes, the cockpit is not too heavy for me to handle single-handed. It is awkward because of its size and shape though: 8 feet long by 6 feet, 3 inches wide. I tipped it off the saw horses where I'd been working on it and moved it with a dolly to the backyard. There I was able to pull it over the grass to position it between the hulls and fit the forward edge to the mast beam:
I got it up to the lip on the mast beam by lifting it from the front with a rope and reaching over the beam with a ladder to pull it into place:
Then I lifted the stern end up high enough to put a small saw horse under it:
With it in this position, I could then set the rear beam in place, tilt the beam back while reaching over it with one hand to grab the top of the motor opening, and lift it up high enough to lock the beam back in place. I really like the way the cockpit is captured by the beam flanges. It's a simple and secure design. In this photo you can see the two 1.5-inch scupper holes I drilled in the aft end of the cockpit for drainage.