The Impreza (all versions I believe) comes
with 5.25' rear speakers fitted via adaptors
This by itself is stupid; A car of this power
and prestige should not come with 'micky mouse' equipment. More so, to my knowledge Subaru does Not provide a 6.5' or 6x9' speaker adaptors for neat
installation and re-installations. Can anyone think of a better solution than
trimming parcel shelf ???

I fitted a pair of 6x9s by removing that phoney blanking plate and creating a couple of MDF spacers, bolting the whole assembly through a couple of holes that already exist in the metal under the cloth/cardboard shelf - and I didn't have to damage anything. The aperture is not big enough, but not too far off, and you won't notice the blindest difference in sound quality unless you have ridiculously sensitive ears. There is JUST enough room to mount them flush under the shelf - don't try and fit them on your own though, unless your arms are 8 feet long. Just get a couple of pieces of A4 and draw up a template, and you're away.

Zip ('93WRX)