I was going to mention that. The H-223 changed the mounting bolt size around '94? Maybe H190 also. Inner Diameter?
Didn't Wayno swap lower gears onto an H-190 LSD?
Again, not sure about the H190 but the R180 ring gears went from 110mm ID to 115mm ID in/around '76, so a 110mm ID ring won't fit a 115mm carrier. Could be a similar situation with the H190