Hardening off help, please?

I'm behind on getting these guys hardened off..our last frost date is June 1, but I really wanted to start this 2 weeks ago and have been too busy. I finally got the plants outside for an hour today in the shade. I have them in boxes to make it easier for me to move them. Is this a problem because they aren't spread out enough or because the box sides come up above some of the shorter plants? 
I also plan to keep them on my enclose back porch from now on, but it is still getting down into the 40s/50s at night. Is this going to backfire on me with the cold? 
I had planned on using a small greenhouse for this and wouldn't have these issues, but there's too many storms every day and I will not be happy if it blows over with all my hard work inside. 
 

you need to have them fully exposed to the sun.

that looks just fine temporarily. after 1-2 weeks i would want you to transplant them out into full sun into their final spots with more room though.

I definitely plan to have them planted within the next 2 weeks and in full sun, and hope for no more snow. I was under the impression that they can't be tossed directly into full sun without killing them. I asked about the boxes in case they're too close together to get the benefit of the sun and wind.