You are taking it voluntarily?! As in you haven't got a yellow sticker?

The proper process as i understand it, is to fill in a modification application form. From there, the DPI will either approve in principal (now go and get it inspected and permitted), or they will flat out ask for it to be engineered. I would hazard a guess and see irrespective of what sprintex say, they'll ask you to have it engineered.

I'll also put a large wager on you not getting coilovers permitted, they must retain a certain amount of the factory droop (i think this was the term used), no coilovers will pass this test.

Unless i've misunderstood your situation, if it were me, i'd be doing the mods, and forgetting about permits/engineers/inspections. and if you get a yellow, deal with it when the time comes.

As for your braided lines, print this page off and show to the inspector, talks about ADRs

Certification | HEL Performance