How do you stack these boxes together I have the edge ez laying around with only My TST on the truck. I was just curious how you would go about doing this. Thanks

Install both boxes normally. The only point of contention is the MAP sensor. Plug the TST into the MAP sensor on the intake manifold. Plug the EZ into the remaining TST connector, then plug the remaining EZ connector into the factory wiring harness.

Be careful not to run the fuel pressure to zero, or kill the stock (and rather fragile) turbo.

Yeah, stacking is great.
Tom, how do you like your FASS?

Tom, how do you like your FASS?So far, so good. Nice and quiet, and still putting out 16psi downstream of the stock filter. I can only drop it to about 12psi or so on an extended WOT run.