Pretty easy to reach the knock sensor from underneath the back of the engine though. Just reach your arm all the way up and push the button in and pull the sensor out. I've done it several times in the swap I'm doing now.
As for the vss, which b16a are you using? If the b16a sirI, then I just took mine off the b16(due to the hydrolics not needed with the crx), and put the one from the d16 on it, and hooked up the speedo cable to it. Hope this helps. I don't have pics of them.