Massive difference in offset, as std offset is 55mm on 2wd and 36mm on 4wd.
Geoff uses on some applications discs, that he simply machines the bell part of and adds alloy bells.
I've been there when in his newer place he skimmed a warranty return pair of discs, by putting in lathe skim one face take out and swap around then do other face, this is a massive no no, skimming needs to be done on both faces by means of backfacing, so the face/s stays constant to the bell.
I've known geoff for years, calipers are great but would find alternate disc bells, or have them straightened before using.
Geoffs monkey fitted a set of brakes on a sierra very badly, such that 100 miles later the metal edge of the outer pad was clonking against the bell, and actually wore part through it, and was wearing through the bolt heads, as they didn't grind the edge of the pads needed to clear, the calipers he reconned also had 2 buggered bleed screws, and when taken apart again had blasting media/grit in them.
tabetha