Trans Kickdown Linkage Guru Sought

so, blue, 2 bbl, and the oranges are for a 4bbl right? the trans arm on the setup i have 318/904 (factory to 87, highway patrol rig) had a longer arm than the stock 225/906 by barely a 1/4 inch, and was about 1/2 an inch more towards the rear of the car....i had to run the slant arm for a while because of floor interference issues with the factory arm. it shifted like a dream but it was a pain to get it to kickdown at full throttle, just short of smashing the pedal through the floor. since then ive "fixed" the floor and now am running the proper arm, adjusted it throttle fully open, arm and its farthest travel towards the rear of the car, now it shifts fine under light throttle, but way too fast under heavy load. driving me nuts.