I have a Pioneer 3100 install with 3 components, BT unit, Sirius adapter, Sirius tuner. Right now I have them in the lower glove box. Any ideas on where to mount them w/o yanking HU ? Thought ablout maybe behind glove box but not sure what I can screw into back there.

 

How about the back side of the dashboard? You could use some NASA-grade monkey tape to hold them up there. What I mean is, remove the glove box and two-sided tape the components to the reverse side of the dash from underneath...

 

Here's the only problem, looks like all kinds of air ducts under there.

 

Lemme see if i have any pics of my dash and I'll try to show you where i'm talking about. There shouldn't be anything in the way where I'm meaning....

 

One trick I've always used was putting them under the carpet in the passenger side. Back when in-dash units had hide away brains, you have sometimes a module for the brain, one for navi, one for iPod, one for XM/Sirius and another for outputs and inputs. I'm pretty sure you can fit at least three in the Fit. Just make sure to use some adhesive to make the stay as far up as possible so they won't get stepped on.