You need to get high compression pistons too...
WHAT WHAT WHAT?????/ say goodbye to headgasket and maybe even the head bolts!!
Ive done a bunch of turbos on various cars and heres the lowdown
Either put 2 copper solid gaskets (not the reccomended route) on and high tensile head bolts OR (and this is the way i do it)
take the pistons out and dish them, then add 1 copper head gasket, use high tensile head bolts and put that all together,
now you need to baffle your sump, and add a return to the sump weld this in or it will **** out like a sieve!
fit the turbo manifold and plumb up the return and feed for oil. this is normally taken from the oil filter housing, if you cant make it work buy an adapter to fit with it ( sometimes you can use the oil cooler outlet for the feed, just make sure you route it back to the cooler BEFORE going to the turbo!!!)
now you need to make sure the inlet side is airtight and pressure proof, use silicon hoses and good quality clamps.
more than likely your injectors will be ok for up to about 5psi but after that id look at upgrading to more flow.
Now the only thing you need is a remap.
HOWEVER i have seen cars running on the original map with a fuel pressure reg to turn the fuel up and had no probs but again after about 5psi youre looking towards a remap.
%psi on a t25 garret or air research will probably make you between 30-40 hp safely, doing the remap and boosting up to 8 or 9psi more like 60 to 80hp. but theres issues with the crank and other engine parts then
Any more advice just holler!