Just as a side note, if you have aluminum drums, they are the same thickness as rear F body rotors. I just measured because I was going to replace the rear wheel studs, and then realized nothing changed as far as spacing.
Interesting & thanks for mentioning that. I have the LS1f-body rears in boxes for their next lease on life under the 'Bu. Previously I just checked w/the current steel drums when measuring the fit-a-ment & knew the track width would change. I have a pair of the aluminum drums sitting on the shelf & didn't think to check them as well. Makes sense the aluminum version would be slightly thicker from a materials standpoint.
I have the 'possible' front wheels in house (not fully committed yet). Once I make that decision, I was going to order rears w/the rear disc set-up dimensions/backspacing target & run a .250" spacer if necessary (likely) for the interim while the drums were still out back. Instead, I can pop the aluminum drums on there & achieve the same spacing. I'll measure mine before closing down the shop for the day & make sure the dimensions are consistent.