I don't have photos, but they're definately not stock. The holes they're screwed into were drilled by someone who wasn't very good with a drill. They didn't bother to tap them either, just manhandled some screws in.
The holes appeared to be stock, though. Just get 3.5's that have metal wings instead of plastic ones, as they WILL need to bend to screw in the speaker, and plastic ones will just break off.
Mine are getting plenty of power, 3.5's are just limited in their hz, I swear there isnt any production of sound below 100hz in this car. Music just doesnt sound very good. If I turn it up loud enough to fight the road noise, the higher notes are making my ears bleed.
The trim that was added (from a newer model) fits fine. You wont have any trouble, it's a drop-in replacement. All you'll need to do is drill holes to mount the speakers, and since you've got a doner car, you can even see where it's best to drill them.
edit: Just found in another post someone saying a boss bass1200 (10" woofer) fits under the seat in their mk1. I just may pick one of these up this week!
edit edit: link:
sub woofer under the seat questions