I recently changed out the rear brake drums on my 1991 Toyota Pick-up with a Trail-Gear rear disk brake kit. I also swapped out the master cylinder with a Advics BMT-051 Brake Master Cylinder. During the installation I found that the rear brake proportioning valve was also bad, so I replaced that too. After extensive brake bleeding the brakes work much better but the problem is that there is excessive brake pedal movement before the brakes engage. I read that installing a 2 lb. residual valve would help but then I read that the new master cylinder already has a residual valve built in. Did anyone else have this problem and what did you do the fix it?