Hmmm, what I think is one of the underlying causes of the OT and NWs is that he needs to be on a more age-appropriate routine. I see that his A times are about 1h long, or less. At his age, most LOs are doing about 1h30-1h45 A times (see here:
http://babywhispererforums.com/index.php?topic=64158.msg476652#msg476652). Now, how this need of an A time increase relates to his overall routine is that he probably started short napping and/or had one long NW (that lasted for ~1hr)? Just taking a guess there as those are typical signs of needing more A time. Then, because of the short naps (which I see he still takes in the PM), he doesn't get a restorative snooze in, so then becomes OT by the end of the day...which then shifts to OT NWs/EWs and being tough to get to sleep at bedtime.
Another thing that I think is happening is that he sleeps so well for that first "nap" because it comes so soon after his "wake-up" time that his body is treating it like an extension of night sleep.
I know you wanted to know how to fit in the feed at the end of the day, but once we tweak his overall routine, I think that will fall into place.
What I would start doing is when he wakes up for the day, increase his A time by about 10 minutes. Very, very gently do this so as to avoid OT. If you think he can't handle 10 minutes, then just go for increasing by 5 every couple of days until he starts taking long naps (we're shooting for between 1.5-2h; 30-35 minutes is OT; and anything from ~40-just under 1.5h-ish is probably still UT).
That said, while he probably will need to be doing ~1.5h A times, his body can't handle a sudden 30 minute increase without becoming even more OT...that's why we want to take this slowly and let him have time to get used to the new A times.
When he's at ~1h30 A times, his day will look like this (adjust per wake-up time):
E: 7
A:
S: by 8:30
E: 10
A:
S: by 11:30
E: 1
A:
S: by 2:30
E: 4
A:
S: 5 (~40 min catnap)
A: 5:40ish
Then feed, bath, bedtime routine in whatever order works for you (I recommend feeding last before bed so as to fill him up the most)
S: no later than 7:30
But, another thing is that as you're doing this, you might notice that his body is naturally transitioning to a 3.5-4h EASY (this happens at about 4 months). Here are some links to help with that:
http://babywhispererforums.com/index.php?topic=63161.0http://babywhispererforums.com/index.php?topic=120362.0Now that I've addressed those things and in response to your original question...while you're making these changes, if he wakes up early from his last nap (which is really supposed to be a catnap anyways), if you think he needs an earlier bedtime, feed him and put him to bed early. I think the post-catnap evenings are very flexible. I think if he wakes up at 5:30, has had a really bad nap day, then yes, feed early and put to bed earlier (say at about 6:30) so that he can catch up on some sleep. If he's napped well that day, wakes up at 5:30, has eaten within 3 hours from waking up, then you're probably okay with keeping him up until his bedtime and feeding whenever you normally would. Does that make sense? It's just that how you do evenings will depend on the kind of day he's had, and bedtime is flexible to allow for good or "off" days.

Since you mentioned you thought it was a GS (which it could have been as there is one at ~4 months), have you seen the NWs taper off? I just really feel that his routine needs to be tweaked to accommodate his need for more A time, and doing that, I feel, will help a lot of these issues.