Hy jomichael, do you know what the master cylinders original application is? If it is for disc/drum brakes, then you will have to install at least one 10 p.s.i. residual pressure valve in the line plumbed from the reservoir that was originally for disc brakes. If you are using drum brakes all around, then no proportioning valve should be required. I always assumed the difference in ports in the master cylinder was to make line cross connections impossible. You can buy port adapters to make your port connections the same. If 3/16" was your original size, there is no reason why you can't use it, hope that helps
