That's weird, you don't need an FMU since youf Vafc hack (vafc+larger injectors) replaces it. Typically, for applications from 7-10 psi, 450cc injectors are good with the vafc or safc. Honestly, I think your original setup was right. I don't know why the other guy said that. That walbro 255lph-HP In-Tank should works fine because you're running low boost. I did my homework and that's setup of yours is what everyone reccommended for a low budget style.