If you have an uneven road where you are braking you will get a pull, happens all the time here in Alabama on these roads. Make sure when you test your brakes it is on a flat road.
With all the hardware replaced then I would look at rear thrust alignment.
With that looked at then I would look at lower subframe bushings, lower control arms, upper strut mounts.
If you are sure that you are not having a piston from the rear drum brakes sticking or siezing then check out the drums again.
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
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