Need some brake info, Please

[jessewebb]

When I bought my truck, one of the first things I did was add power brakes. I remember one of the questions on the order form was, is the proportioning valve for a front disc and rear drum or a front and rear disc or a front and rear drum. My truck has been changed to the five lug disc brakes up front and five lug drums on the back. So I bought the power brake set up with disc up front and drum in the rear. Now I 'm changinrg the rear drums, to rear disc. Question: Do I have to change the proportioning valve?????