Rear Shelf Speakers in '93 90csq?

[KHCrossley@aol.com]

Anybody have experience in installing 6X9 speakers in the rear shelf of a 1993
or later 90 csq?  My wife's car has the stock factory rear door mounted
speakers which the local stereo equipment installer disconnected from the
integrated amplifiers when he couldn't eliminate an ignition noise after
installing an Alpine stereo/cd unit.  The end result is some pretty marginal
sounds coming from the back end of the car.  I would like to install new
larger speakers in the rear shelf with an external amplifier, probably a 30X2
unit.  The steel sub-shelf has a significant amount of stamped deformations to
increase the section modulus and I am a little concerned about cutting big
holes in it to accommodate the speakers.  I would appreciate any thoughts on
this issue.  TIA!
Regards, Kent Crossley,Portland, Oregon
'91 200q 
'93 90csq