All those procedure and advice assumes you have the factory original kickdown set up, original transmission and stock engine. Once you have changed the powerband, torque convertor or anything in the engine. Upshift and downshift points will not be the same.

If any lever has been changed to another ratio. Most set procedures will not be 100% correct.

At a minimum Full throttle when the transmission lever is almost bottomed out. If it shifts too late loosen it off.