to prevent people asking same questions all the time. if you know more stuff add it up. definate stuff too, i know some celica diffs will fit but there are differences that i don't know of for sure so i haven't put them in.

S Series = ADM = no LSD available
T Series = JDM or T18 + others = plenty of LSD's available (KAAZ, Cusco, TRD etc)

S Series 8 bolts carrier to axle housing
T Series 10 bolts carrier to axle housing

S series = ADM AE86
T series = JDM AE86, T18

when fitting a T series diff you need a shorter rear tail shaft either out of a JDM 86 or a T18. the rear shaft for a t series is 20mm shorter than that of an s series

ADM AE86 760mm, T18 740mm

Ke70's have a borgwarner diff different to S and T series. both S and T series will bolt in but an s or t series tailshaft must be used.

tailshaft and diff combo's (assuming you have fitted 4AC or 4AGE and using T50 box)

AE86 + T series = ADM or JDM front half + T18 or JDM rear half
KE70 + S series = ADM 86 or JDM 86 front half + ADM 86 rear half
KE70 + T series = same as AE86 with T series
AE71 + S series = same as KE70 with S series
AE71 + T sereis = same as AE86 with T series