Rear disc are easier to work on than drums with all those stupid springs
If you end up doing it, keep in mind that the discs and internal e-brake shoe assemblies are the same on gen5 Celica GT-S set-ups. I found this out by accident last week while working on both of my cars at the same time...I don't believe that the Hollander interchange lists them as being identical, but after examining them, they seem to be.
I mention this because it would likely be easier to find aftermarket rear brake parts for a 91 Celica than a Camry of the same vintage.
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1990 5spd V6 Camry (Still kicking at 393,000km) 1991 Celica GTS -- Pappa needs a 3SGTE...and AWD for all this friggin' snow
Honda my A$$, you just can't kill a Yota...