I have a 700 behind my 468 in my 70 Wagon. The only time mine shifts a little hard going down is when I have it in third. When the cable is adjusted ---Very close--- It should up shift close to -- 13-- 36--55 MPH.
Your cable should be mounted to the carb. pointing to the rear at 58 degrees and the piece that the TV cable snaps onto at the carb should be close to --1 and 1/8" from the center line of the throttle shaft.
The piece with the square hole in it should be-- From the front of the square hole to the center line of the piece that mounts on the carb and looks like a " Nail Head " . Should be very close to 4 & 3/4". ( engine off throttle relaxed).
If all measurements are correct-- Slide the TV cable to towards the firewall, NOW very SLOW, From inside your car, PUSH down SLOW and listen,,,,, If you hear a CLICKING sound the TV cable is setting itself.
WHERE did I get these measurements. I found a G.M. engine at a bone yard........... Got the yardstick and a crayon and did mine like the factory.
My 700R4 has around 40.000 miles on it. My 700R4 is out of a 454 mid eightys Suburban
PS.-- Oh, Did I mention,,, I drove my first 700R for about a half hour with the TV cable " Out of adjustment " ,, Total destruction of that transmission. Then I did my homework. This trans. has been just fine for nine years. So I believe ( Due to nine years and NO problems ) I think I got it RIGHT.