hi mate, firstly the impeller shaft should have a small amount of up and down movement..(less than 1mm in most cases) NO back and forth movement, some turbos can move up and down quite alot when they are hot, expantion and all that...the reason they have a small amount of movement in them when they are not in use is because the oil needs to have a space in which to move around the bearing at pressure,

secondly, ford used the T3 with a .48 housing (size of exhaust housing) on escort rst and saff cossie

T25 on fiesta rst, .48 housing
T34 on escort cossie (big turbo) with .63 housing
T28 on escort cossie (small turbo) with .44 housing (i have this one on my S1 with a roller bearing conversion)


all you really need to do is drain a small amount of your coolant to get the turbo off, you dont need to drain the oil, however if fitting a new or re-con turbo it needs new oil anyhow,