I tied out a new install location on the duo now that the amps are pretty low profile. Replaced a different amp with mine:
http://imgur.com/a/gXniJIgnore that hole the wires are going through. The previous modder drilled that and I just used it cause it was there. You can just bring the wires up on the back of the PCB, directly behind that hole. I also put some kapton tape on the shield below the amp just in case it would ever fall (which isnt very likely). There is still plenty of clearance between the caps on the amp pcb and shielding.
I will probably take some more pics when I do another one that doesn't have extra holes in it.