The kickback in the steering you are referring to is actually a hydraulic reverberation caused by air still trapped in various places in the power steering system. This will start disappating with every passing mile of actual road use (as the air in the power steering system works itself out), and requires no further action or concern.
As far as going about the installation of a second dedicated low pressure return nipple, Kevin Oeste covers this with live video! You can go to our multimedia pade and check it out - the first video on the page below the automated slide show titled '70 Pontiac Trans Am "Splitter" hydroboost install:
http://www.hydratechbraking.com/Hydr...ultimedia.html
It doesn't have to be an AN-6 nipple as shown, and can simply be a push on hose barb / tube, as you are only returning about a tablespoon or two of fluid back home to the power steering reservoir every time you let off of the brake pedal.
If you are confident that you do indeed have the low pressure return line T fitting installed as instructed, or have run the low pressure return line backpressure test (as specified in my previous post above) and find no problems, I suggest you do nothing more than go put some miles on it. Actually, I caution you about opening the PS system back up unnecessarily, as this will re-introduce air back into the PS system (which is counterproductive as we are trying to rid the system of air).