Everyone calls the big turbo escort cossy turbo a t35 because it half of a t3 and half of a t4 hence t3 1/2!!! however the actual turbo is called a T34-(t3&4 together). The turbo has on it TBO34 and the proper garrett part number is a TB3403 w/c (water cooled).
People also call the small turbo'd cossies T25 as the turbo is fairly similar looking to the T25 (fiesta turbo) but is actually a T28 or TB2807 w/c which is completely different to the T25!
RS500 is T4 (T3/T04E w/c)
2wd cos is T3 (TB0361)
4wd cos is T3 (TB0384 w/c)
Fiesta turbo is T25 (TB0250 or TB0239)
RS S2 is T3 w/c (TB0355)
RS S1 is T3 (TB0345)
RS200 is T04E/T31.