Keep a diary of your latest build here.
I had the same frame, AMF from the 60's, I just went with narrower tires, 2.00 instaed of 2.125. I have used a 2 x 4 and hammered in between the frame members up by the kickstand, the squeezed the dropouts back together, but be careful and do it slowly making sure everything is lined up exactly right. The wood should sit right where the tire will. It's all good steel so it should bend and look good.
ended up switching out the handle bars tonight the wife liked the look but didnt like how the first ones fit so I went with a set of wider set that I ended up painting since the chrome wasnt the prettiest