When accelerating with my 53 F100 the differential wants to twist. I would put traction bars , but I did a differential flip & I don't Think traction bars would fit without a lot of modification. So I was planning to put a bump stop above yoke of the differential. Do you think is a good solution for my problem?

 

So your differential housing now sits above the springs instead of below is what you mean by Flip. The way a passenger car would be of that era. Traction Masters ( brand) were very common, but we went to the junk yard, got a couple of Buick rear sway bars and made our own. Pictures of your set up ??