Ultra budget low boost help

[Grocerygetter]

Hi , I have a 84 533i that I got recently . Love the car but I’m exploring my options to obtain more hp . I’m looking into a low boost , non inter cooled stock Motronic set up. I do plan to do head studs and injectors, but my questions are .
What is the max boost the Motronic can keep up with?
What size injectors ?
Do I run afm In front of turbo (pull through) or after turbo (blow through)?
Do I need a fuel pressure regulator?
Also anything else anyone feels I need to know , thanks