Proportion valve and Residual valve?

Have 74 Duster with disc on front already and upgrading to 11 3/4 front Disc's from Dr. Diff and have an 8.8 with the disc's on the rear.

Would it be wise to put Proportion valve and 2 lb. residual valves on the system sense it is disc/ disc?

Have read a lot on here where some need it and some do not. Is it a try it and see what you have and then go from there deal or is it better to get the stuff and have it on hand so do not run back and forth to the parts store or ebag and wait?

Also safety is my concern since I will have my kiddos ride with me.
Thanks!!!!

Will check back tonight going to work on car before it gets Hot!!

Idaho had a link in a thread about brakes and setting them up and I lost it. It had my answer in it I think. :banghead: