I understand the proportioning valve in your system. It allows fine tuning of the relationship between your non-stock rear brakes and apparently stock front?
You've either included information we don't need, or haven't included enough.
You'll want to run your brake lines similar to stock, inside the frame rails and secured to crossmembers. You should have no trouble with them hitting the trans or exhaust unless its at the bellhousing crossmember.
How are you mounting the motor and transmission?
