I have a 86 T-A with a new 305 lg4 and a rebuilt 700R4 tranny (I think 86 also), when I am at idle (600 rpm) and shift into drive the tranny hits REALLY HARD (almost hard enough to spin the tires) if I shift into reverse first then into drive its nice and smooth. is there anything I can do to eliminate this, I don't want to tear something up in the driveline ???