1970 Plymouth Fury shiftingon a 904 Tourqueflite

I Actually have a 51 Plymouth Concord, not listed on your site. I have installed a new 904 trans, street and strip model. It shifts fine except when going from 2 to 3, it doesn`t shift untill about 3200 rpm.I beleive I have the trans pressure arm adjusted right. I have it that at full throttle, the trans arm is almost to the rear of it`s travel. Is this the correct way to adjust this arm , or am I doing something wrong ? thanks