So for the LBP Rotor I measured the Rotor Hole dia which is about 2.90". The Rotor hat area is about 6" Diameter and tapers larger at the rotor surface.

The hub inner register that goes into the rotor is also 2.90". The Hub Flange diameter is about 6.17". The hub diameter at the wheel hole is 2.70". This hub flange is also about .020" thicker then a SBP A Body rotor. Thickness where studs go through hub.

I took apart an older A Body SBP rotor that was heavily worn, but had 7/16 Left Hand Studs. KH Stamped. You will love the picture as the rotor was so thin on one side it pushed the hat area through the rotor when I pressed it out.

The Original KH SBP Rotor Hat area is very similar in all dimensions as the LBP Rotor. Same hole size for hub.

Also this Hub had the Same symbol as the LBP, a small O inside a box. Not sure if KH had their own foundry or subed out the casting. Did have K/H Letter as you can see.

The SBP Hub has a 5.76" Flange Dia with 2.30" Wheel register. The hub rotor side Dia is the same as the LBP at 2.90" So I can swap hubs between the two rotor, the stud holes just do not match up. Plus the LBP Studs have a .625" Knurl, while the 7/16 studs are the stock .56?" Dia.

Basically the LBP Hub is a beefer hub like B/E body two pieces but with all the other attributes/dimensions of the smaller A body hub other then the changes needed to be a LBP hub.

Pictures are the Original KH SBP hub I took apart this afternoon.