New Filter/Pan Install Th400 Transmission 

To my knowledge thats a vacuum modulator. For me at least its connected to the back of the intake, it uses the motor vacuum to control the timing of your shifting in drive, theres a screw on the inside of where that tube connects that will advance or retard the shift timing depending on the way tou turn it

That's a good idea using that spacer. I'm getting ready to change mine going try a spacer . I don't like how it just kinda hangs there

DO NOT USE A SPACER FOR THE FILTER, it’s made to lift up and down

That's a high flow filter