Amp mounting location?

[doubt at inwave.com (Nate Mellom)]

I'm planning on swapping my ICE system from my Quantum to my '88 for the 
trip to Cincy, and I need to mount my old-school Alpine mono amp 
somewhere to run my spare tire sub.  Where's the best location?  I'm 
looking for mostly hidden, with no hinderance to cargo hauling.  I've 
mounted amps under front seats before (in other cars), and the amp isn't 
that big, so that may be an option, but where have you guys stuck 'em?
TIA.
Nate