Thanks for all the great suggestions. For now, I've decided to just dress him without really giving him much of a choice. Like, put the t-shirt on over his head, unzip his jammies and get the arms right out of the jammies and into the shirt. That's worked the last two mornings.

I'll reread all the posts and come up with a better plan. I've tired a lot of the ideas but for right now I just have decided not to fight the battle and just do it for him. Glad to know I'm not alone and others have had problems.