Hello, I installed RSD's Drum to Disc conversion kit and their complete brake line kit on our 68 GTO (non-power). After the installation, I bled the brakes at all wheels and the air seemed to be all out, but the pedal braking is spongy. I did the bench bleed procedure on the Master Cylinder before I put it in, but I had difficulty installing it since the proportioning valve and brake lines were coming in contact with the wheel well. I finally got it installed, but my guess is in the process air may have got back into the master cylinder. Is there a procedure to get the air out of the master cylinder without removing it from the vehicle? If I simply continue bleeding at one wheel like the driver's side front closest to the master cylinder, will the air eventually come out, or would I need to disconnect the lines on the master cylinder connected to the proportioning valve and effectively do a bench bleed on the vehicle? Apart from the fact brake fluid would leak out the side of the master cylinder, I really don't want to disconnect or remove anything if at all possible in fear it would allow more air into the system. Any suggestions would be deeply appreciated. Thanks!