SSBC A-153 Front Drum to Disc Brake Conversion - Non Power - 71 Demon 340

It’s not crazy to think that could have an effect on the steering shake. It wouldn’t be my first thing to suspect but that doesn’t mean it’s not the problem.

When is this shake occurring? All the time? At certain speeds? Only when braking?

The other thing is, you’ve shown that the studs aren’t centered, but, is the hub itself centered? Is the center register of the wheel tight on the hub? The factory wheels are hub centric, aftermarket wheels are often lug centric. If the wheel is lug centric then the studs not being centered could absolutely cause the wheel shake. If the wheel is hub centric then the studs not being perfectly centered might not cause the shake as long as the hub itself is centered. Which is not to say that the lugs being off center isn’t an issue, just maybe not THE issue.

It certainly shows lousy craftsmanship, so, it might not be the only problem with those rotors and hubs.

Other stuff to check would be that the wheel bearings are properly seated and have the correct end play, and any run out on the hub and rotor.
The shaking occurs while driving but is worse at around 40-50 mph... not when braking. The pictures you see had the same test done to ensure the hub was centered and they are perfect. I will need to see from my installer if it is hub centric or lug centric as I am not sure what that means exactly. He did mention that he tried to perfectly center the wheels as the lugs do not go thru the wheel holes of my Cragers. I never had this problem with my drum brake system and the same wheels. Hoses, brackets, etc. all had to be modified to make this system fit/work. SSBC even had to make a castle nut because the one they provide didn't work. I do not know alot about this as I am sure you can see, but my guy has had his shop for 40 years and has owned about 30-40 Mopars so i didnt see this being an issue. I should have went with my gut and went with the bigger bolt pattern Willwood set up. He had used SSBC on many b-bodies in the past with no issues. Sick about this. Next step would be to go back to the old drum set up I guess.