I personally dont like slack in the throttle. I want it sharp. When I was adjusting the throttle cable i found if i took as much slack out as posible without causing high idle, rev hang, or tps >0, the feel at WOT sucked. Theres a rubber pad on the pedal that prevents you from putting too much tension on the cable when the throttle hits the WOT stop. Engaging the pad too much makes you question wether you re at WOT because you feel the squish long before you hit the pedal stop. Engaging the pad too much is going to happen if you have too little slack.
I would suggest using a piece of wood to hold the pedal against the pedal stop. Then turn the adjustor nut until the throttle hits the WOT stop. Let the pedal off the floor and put one to two turns on the adjuster nut to engage the pad some at WOT. Lastly make sure theres still slack in the cable.
I bet its close to what the FSM specs for slack.