K30 / K5 Frankenstein: braking problem

[bcoke]

My braking is super touchy right now because the back drums are braking way before the front discs. Turns out I have a master cylinder, proportioning valve, and front lines for a K5, but the axles have been swapped out (owner before me) to 1 tons, which I’m guessing are from a K30.

So looks like I need to go find an MC, prop valve, and line dimensions off a K30 to match the bigger axels, right? Anyone have any advice? Or done this before and been through challenges they can share?

Any help is appreciated!