Thanks essence! That's exactly what we've been doing - a cycle of eat/change, activity, sleep. When he gets fussy I know he's tired so we swaddle, walk/rock and sing until he's asleep. I think the problem becomes sometimes he goes to sleep and I put him down and he's right back up (doesn't do this at night). So I think his "cat naps" aren't enough and it's all catching up with him around 6pm. Then he physically WON'T go to sleep no matter what! We swaddle, rock, white noise and sometimes a pacifier (he hates!). We do a bedtime routine of bath, eat, book, but he still is just a madman. This week I'm going to just stay home and every hour he's going right back to sleep.
He's SO happy when he wakes up in the morning or has a great 3hr nap in the afternoon (usually sleeping on me!). He is a great sleeper at night once he goes down. It's just a lot at 6pm because my husband rarely sees the sweet boy during the day and both of us are exhausted by then too.