Distribution block question.

You will need the unit off of the disc brake car. Your drum brake block will not work with your disc brake setup. Sorry for the bad news. Using a set of line wrench's always makes for an easier removal of rusted lines. Use some PB Blaster on those lines as well. The proportioning valve, the unit on the disc brake car, is made of brass so you shouldn't have to hard of a time with the correct tools as the lines shouldn't be rusted fast.