please help brake question

[workinprogress67]

hello, i have a 67 shortbed and re-did the brakes.. front discs, master cylinder, prop valve (disc/drum) from cpp, new drum hardware and shoes for the rear and the drums were still good and all stainless steel brake lines from right stuff. my question is.. i saw that stacey gearz show and he said not to use brass with ss line, only oem lines and instead use AN fittings for stainless.. my brakes SUCK and i used brass. could this be the problem? manuel brakes, no leaks, gravity bleed the brakes. i believe the front is grabbing too much more than the rear

Thanks for your time, Joe