I've posted my fix on the modifications section. I think I was successful. Check it out.
http://www.zggtr.org/index.php?topic=13655.new#newCopied from other post. Photos are at that post.
I have accomplished what I set out to do, which is to eliminate the rear link to the front and the ABS system. The first thing I tried was to plug the holes on the ABS block and replace the rear line with a straight line from Galfer, see "block plugged" photo. After a test ride of hard braking and trying to engage the ABS on the front tire, the "ABS Error!" flashed on the display. I think what happens in that situation is the computer can sense that no fluid pressure is being allowed to go out of the ABS block to the rear brakes. Next I reattached some of the rear brake lines and then put my bleeder plugs into those lines, see "hoses plugged" photo. I attached clear hoses to those bleeder fittings and flushed the lines with a vacuum pump. I'm not sure if I got all the air out or not but the brakes feel fine.
I then test rode it again and everything works as expected. ABS on the front works perfectly. Under sudden braking at about 40mph I felt the ABS trigger and pulsate down to a stop. No more sudden braking and diving unexpectedly when applying front and rear together. The brakes feel perfect to me know. I then found some wet pavement (didn't want to ruin new tires on dry pavement) and locked up the rear several times to make sure that it wouldn't trigger an "Error" on the display. No problem. I think it is my solution.
The plugs that I used, see "bleeder plug" photo, were obtained from Galfer when I bought my rear Stainless line. The plugs needed to have a slight bevel machined into it to look like the original flare fitting to mate and seal properly, see "Flare fitting" photo. All we did was put it on a lathe and machine it with a 90 degree drill bit so that the plug had a 45 degree edge on it. It might be accomplished by putting it in a vise and using a drill bit of your own to make the concave surface. The material is chrome plated brass and I don't think it needs to be a perfect fit. It will deform to fit and seal on its own most likely. Just don't make the bevel too deep. You don't want the plug to bottom out before hitting the cone first where it will seal.
After having done it all I have realized that I could have left the original lines in place, disconnected them at the spot under the tank, plugged them as I did and bought one more flexible line like one of the ones in the photo "Hoses plugged". I would then loop it to connect the rear master cylinder to the caliper using the existing lines that were left in place but had been disconnected from the flexible ones in the photo.