[Alan Roehrich]

I've been told it must be in the stock location for the combination being run.

I'd guess, just a guess mind you, that the stock tray must be used, I don't remember ever seeing an aftermarket tray in the stock location on a stocker.

Ask Gracia or Bachelder, and get it in writing, do it by email if you like, and keep a copy with the car. You can use a heavy duty hold down, and so long as you do that, I'd say the stock tray will be sufficient.