I remember napping after school while in kindergarten, too, but my kids gave up naps much earlier. All kids are different. My oldest stopped needing a nap when he was 3, my middle child just recently stopped at age 2.5. Notice I said 'stopped', not 'no longer needed'. :-) She still needs a nap but we've given up and gone to 'quiet time' because she won't fall asleep. I can make her stay in her bed for an hour but I can't force her to fall asleep. The baby, of course, is still napping like a champ (9 months). :-)
As for your situation. I was in a similiar situation. At this time of year, when my son was 3, I was apprehensive because he was supposed to start at the special needs preschool in the fall (he turned 4 in the summer) and he would be in the afternoon class. (12-2;30pm) During the summer, though, he outgrew his need for the nap and he was fine for school. There were still days when he'd come home and crash for 30-45 minutes but I always woke him up before an hour. If he slept more than an hour it threw off bedtime. During this time, we moved his bedtime to 7pm so he was usually sleeping by 7:30. That seemed to help the most. He was very consistent at waking at 7:30am no matter what time he went to bed -- and 2 years later he still does. He just needs at least 11 hours of sleep each day and since he doens't nap, he needs to get it all at night - 8pm-7am (can't sleep later because the school bus comes at 7:30).
Have you tried putting her to bed earlier to get her to sleep later? It seems very counterintuitative, but it does work with most kids. When my son was very little, we had him asleep by 8:30 or 9pm and he >never< slept past 6:30. As soon as we moved his bedtime to 8pm he always slept until 7:30am. You can also make sure the room is dark in the morning by buying room darkening shades - they work much better than room darkening shades, IMO.