Getting ready to put this together --> 71 Duster 383 /auto - SS springs - 8 3/4 with big bolt pattern and a choice of 73-76 A body disc or F M J body disc brakes. I like the 70s high & mighty looks so would there be a preference in spindles if you're going to crank the torsion bars up. Now let the begin!

It's an A-body, so why not use the A-body spindles?

No real difference in ride height. I would use the "A" body spindles in your case.

There has been alot of debate and crosstalk about the pluses and minuses with each knuckle. The B, FMJR body knuckle has one advantage over the A knuckle, but I have read that it only pertains to Camber Curve at or near full suspension compression. Since you plan to go High boy style, any minor advantage the other knuckle may have, the best choice for you would be the standard A knuckle.

Thanks guys....I just bought a 74 A body spool mount K frame and it has the disc brake setup already, so I guess A body it is........