Get a Nistune doughterboard soldered into your ECU. Skip the SAFC and do it right the first time.
The 550cc injectors are a good idea over the 370s.
Get an ACT clutch or something that can hold 300+ lbft of torque.
Your stock internals are fine.
You need to drill and tap the block for the oil return.
You can get the oil from your oil pressure sensor port, use a splitter, idk what people are using these days, but you need something with a port for the stock sensor, the turbo, and an oil pressure gauge.
You need an oil pressure restrictor. There is a writeup somewhere on everything you need for the oil feed lines.
Get a mechanical oil pressure gauge.
Get a boost gauge.
Get a wideband.
I suggest a 3" turbo back VRS exhaust.