The GT-T and GT-TR were the TA63 with 1771 cc 3T-GTEU and plain bodies.
The GT-TS was the TA64.
My info says 220 homologation TA64's were made, plus a handful of custom made rally cars.
The road going versions were 1791 cc 4T-GTEU while the rally versions were 2090 cc 4T-GTEU (ie stroked).
All TA64's (road + race) had the body extensions.
Practically any picture of that generation Celica in a rally would be a TA64, especially from the African Rally or WRC.
All were coupes - no liftbacks.
All road going versions had a W55 gearbox and 4.100 F series diff.
http://members.iinet.net.au/~stepho/celprod.htm#cel63pr
http://members.iinet.net.au/~stepho/celprod.htm#cel64pr
- Stepho