We have a Cornus Kousa planted in totally full sun and it's doing OK. It's been there for about 6 years now. It took a little bit more babying in the beginning (with regards to watering) and it doesn't bloom quite as much as other Kousas in the area that have PM shade, but it's doing it's thing and has a beautiful shape to it. Best of luck!

I will plant the Kousa. The nearest nursery with these grows them on-site. Owner tells me that they are about 6 feet tall and the tree dug with ball and burlap will weigh about 350 pounds. Typically working just by myself, I doubt that I can lift that much anymore, my best ever was about 550 pounds, 45 years ago, and that only about 6 inches off the floor. I do have rear tractor platform to lower from truck bed to the ground. How do others (or the pros) handle these into the new hole? Chain around the trunk would really damage the tree, probably fatally.

People. I'd say about 3 should do it.
The last thing anybody wants is a hernia from lifting more than one person should. I don't mean to sound all wimpy but health is all some of us got! I know I guard mine!
A tree that size is quite an investment, so take the time and do it right. Be sure to save the receipt!
How do the pros do it? I think they have equipment. I remember at a nursery that I worked at a few years ago, they had tree dollies, trucks and trailers and plenty of workers (including myself). It was also a landscaping company so they also had all this equipment that was used in landscaping that they'd use also in the nursery (like a mini-loader/bobcat that could go in and out of back-yards with thousands of pounds of stones, plants etc.).
Will

That rootball weight doesn't sound right for a 6' dogwood. Is this a multi stem or something? What's the caliper of the trunk?

B&B trees in a wire basket often have straps for lifting with a loader or forklift or by hand. The straps are the same material as automobile seatbelts. Very tough.

I would suggest not planting anything under the powerlines. It sounds like you're aware those are easements that could be dug up or paved over at any time.