Wow reading your post bought the memories flooding back....things definitely have improved!! I had the opposite evening to you at that age, DD would stay up until midnight and then sleep through until 7/8ish. The thing with spirited babies is that they are almost impossible to get into a routine and yet they desperately need some sort of structure
Evening is a nightmare as they have been super alert all day and then just don't know how to switch off, my DD never napped and I wondered why pp said newborns just sleep and eat!
It was actually around 10 weeks I finally got a bit of a handle on it and watched for DD's tired signs much more closely, I started following a loose easy and realised if I put LO down for a nap at the first eye rub/yawn she wouldn't fight so hard. Babies here in Denmark nap outside and it was winter at the time and within 3 days I would only have her leg in her snowsuit and she'd be asleep! Can you introduce something you LO can associate with going to sleep?
As for now my DD is 10 months and goes to bed wonderfully, she loves her bedtime routine. We are currently having a problem with 1 NW per night but it is probably due to OT which spirited ones are prone to at all ages. Like Deb's LO Leorah is also a 6am riser but these little guys have so much to do, so much to see
If I was to give any advice for your current situation it would be keep the afternoons as low key as poss, definitely use a sling, maybe rethink the bedtime bath if he is very tired, this can be stimulating for a spirited one at that age and get him to bed earlier.
Now on a positive note we are so lucky to have these spirited babies. I used to be so envious of mums that had babies that slept all the time and barely squeaked but now I am reaping the rewards with my cheeky monkey! She has so much character compared to some of her baby friends and is so alert and clever, a great problem solver, charmer, drama queen and has a fab sense of humour, all at 10 months! Everywhere I go she melts hearts by playing peek a boo from her pushchair which I have to have as upright as it goes and she still tries to stand up and turns around to look at everything, no lying down watching the clouds for my little diva lol!! So what I am trying to say is that spirited kids are hard work but you get so much back for it. I read in one book that some babies are born with such huge personalities that they don't know how to handle them, we just have to give it time for their systems to catch up. Try getting a better afternoon nap out of your DS by putting him in a sling and I am sure you will see improvement soon as he developes.
Big hugs to you and your LO and all the other free spirits and their tired mums