Woott im trying to help you read my thread.
I'm currently doing exactly this, theres a lot of general info people say which isnt necessarily wrong its just half the info.

Without repeating my whole thread here this is the obvious things I found out the hard way:
- t25 is a flange not a turbo theres heaps of different sizes some too big some too small. Best sized t25 flange turbo i could easily find was off a r32 twin turbo gtr. Exact specs are in my thread
-draw through setups are easiest and cheapest for a basic build. Catch is turbo has to be carbon sealed. That gtr turbo I mentioned can be rebuilt with one
-manifold prices vary massively and arent readily available. Cyclons8 (Chris) is making mine his prices are the best youll find
-1 3/4 " SU is cheap and works well for drawthrough youll need a pro tune. That SU came off certain range Rovers

Costs
Chris manifolds exhaust and inlet budget at least $750
turbo $150-1000 depending on condition
Carbon seal kit $80
Su free if you know where to look
Tune $450