First I've been very deliberately working on "down" with a significant wait time for him to clam down before he gets rewarded or released. This is particularly helpful when he's trying to ask for play and nosing us or jumping around excitedly. We then reward with a game of fetch where he can run around and enjoy the play he was seeking in a constructive and positive way. We also work on dropping the toy and giving treats (a little light training with treats and play rewards). If he ignores our 'down' cue and hand signal then we leave the room (because turning our backs doesn't work) and return as soon as he sits, lays or stands calmly. We then resume where we left off. This has probably made the biggest difference because it was taking the most extreme excitement (bounding around trying to incite play) and turning it to calmness (laying down until calm).
Additionally I've been working on how I deliver treats. Sprocket isn't exactly the most gentle dog when it comes to taking food from your hands. So I've switched to exclusively setting it on the ground. I have not allowed him to mug my hand as I set the treat down. If he does I pause until he moves away then I proceed with setting the treat down. It's made him much more calm when it comes to receiving treats.
Lastly I've been massaging him more. I know, sounds silly right? Well, Sprocket has never been big on snuggles and petting. But, when he's calm he does enjoy a good rubbing. So, when he comes up to me calmly or when I see him being chill - say on the couch - I'll go over and give him a rub. Typically it's a neck and shoulder rub just like you and I would like and would feel more relaxed afterward.
Tiny little extra things: We aren't raising our voices which avoids inciting any excitement. I've been specially using a quite calming voice - the sort you might use to calm a crying infant. We've also taken off his collar. No more collar around his neck removes our temptation to grab it. We also returned to bed time in kennel instead of his bunk bed.
It's getting better but we still have a ways to go. Next thing I'm going to add it surprise treats to capture calmness. Much like the random massage I'm going to catch him being calm under his own choosing and give him a nice chunk of hot dog or similar. I'm also working on decreasing his reaction to stimuli - such as the nail clippers.
So far so good. We'll keep working on it.