No... it's not too late... It may be more of "spring sowing".. .but i too am still sowing and you are a zone colder than me.
I dont think you'd want them in full sun all day. but then, mine are western exp. [i've got about 40 or so out of 103 germinated] I do find I am watering almost dailly with some of the containers.
[I do find it odd that some are completely dried out where others are not, and they are in the same location]
I started my daylily seeds and iris seeds in Oct. 2009 in a plastic shoebox. They began to sprout as the weather warmed. They are now transplated into my coldframe to continue to grow. They will spend the winter in there.
Edited to add that if your seeds need cold stratification to germinate, I would suggest it is too late to WS them. Place the seeds in a baggie and store them in the fridge to use next year. They will keep.