I think you'll be able to hit your 4000 goal depending on your fuel....With e85 these 1.5xtr's spool roughly the same as the 20gxtr but make more torque.
Yes, the process west sti hose will work with this turbo.
I'd definitely get the 3" inlet, it will help out with spool. The best fitting 3" inlet right now is the AMR piece but you will need to delete your tgv's to make it work; KS Tech sells a nice kit if you don't have time to port/polish the insides.
I'd add a 73mm ks tech intake, fuel pump and ebcs if you don't have it and make sure you have new gaskets for what you're pulling apart; other than that it should be a pretty basic swap.