8 3/4 large bolt pattern?????

You could get lucky sometimes with those early A100's having a posi too.....they were close in size but had the pads on the top side.....easy fix.
Got lucky this weekend in the 4 Corners Area of our Country with an 8.75 with a 489 Center that came off an D100 I believe.....the perches are indeed on top and the axle housing from axle housing flange to axle housing flange is 59 1/8 long.....If I cut out the 3.5" where the perches currently sit - I'm right at an A-body width...(Close to an A-Body width)

Moser Engineering shows it offers Axle Housing Narrowing for $195 so unless I find a reputable shop that can do it in this area, I might go Moser route.....check the van/truck axle racks if your local JY has one....I did and found the smooth back just staring up at me....

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