Right now, I am planning on replacing the stock K03 with a GT2871 when the stocker dies.

I have already installed an ER FMIC and was going to use GIAC's PC16 software.

Installing a wideband A/F, adjustable FPR and an MBC so that I can get it dialed in.

What size injectors should I plan for (440's 550's).

with the K04, all I need is the turbo and injectors (already have the fmic and software) with the disco potato I will need the turbo, 650cc injectors, adjustable fpr, wideband AF meter, probably a Boost machine mbc, a new MAF and and some dyno time to dial it in.
All for a daily driver.