Trust me - turn off your power for a couple of weeks, and give you no options - you'll become a day person

Heck - I bet I could turn you into one in, say, 4 days

I'll take you outside in a tent, I'll wake you up, say 7:00am the first day, and I'll make you do physical work till your ready to drop at dinner time - say, 6:30pm - you eat, clean up, and are so tired you fall asleep. Wake up naturally the next day, and have so much work to do, that you can't hang around - run yourself ragged again - till your ready to drop right after dinner - the next day, we'll wake you up, but take it slightly easier - so that your mearly tired at 6:30 - By the 4-5th day, you'll be glad to sack out at 7:00pm, and if your not exhausted, 10-12 hrs later, you'll wake up - and then start working

The trick? NO CLOCKS/WATCHES, no TV, no books, no "time" cues except daylight