it also pends on set up blow through/ draw through
if u doing the easy draw through set up u will need 2 change the front oil seal in the turbo to a + seal. if not the turbo wont last very long with fuel runing through it, seems 2 perish the front seal which will lead 2 constant oil drop in motor and turbo will have heaps of play, and will blow shlt loads of smoke under load.
there are some turbo's which come out with a positive front seal like the Rayjay turbo, older type seem 2 all have them but any turbo reco shop can supply u with new seal, on the turbo u choose,
hope this info heaps abit,