RE: Daimler chrysler and warranty
My D35 had a rubber plug, until my buddy made me a diff with skidplates that had a metal plug.
The 8.25 is pretty flat at the bottom of the diff, compared to the more round D35. The 8.25 also has a large flat area cast into the diff above the pinion.
If you can compare it closely with your friends D35 and it's not similar, then it's an 8.25". The 8.25" also has thicker axletubes.