Single resevoir to double res Master Cylinder

http://www.classicindustries.com/mopar/parts/md2274.html I found one. OEM. Damn pricy for that little guy Ok, it says to use in conjuction with proportioning with vehicles with front disc, and rear drums. I have 4 drums. Will this work for me? I just wanted to put a double resevoir in place of my single one.