Narrowing an 8 1/4" rear end, how is it done?

How is the overall installation of the GM 8.2 axle? Is it one of the 10 bolt 8.2 axles or one of the BOP axles with the 12 bolt cover? If the installation of the existing axle is well done and operational, redrilling would be very simple to do. I don’t see your combination breaking that axle, and C clip eliminator kits are available, too.
Drill Guide